I would like radCloudUploader to be able to integrate with DropBox (and skydrive?) 
As my client has a large investment in DropBox (cos it works on mobile), but I want to be able to upload documents to a given project (subdirectory) via a single interface without giving them total access to that directory.

I would also like to have some integration to a search service such as Azure Search
https://msdn.microsoft.com/en-gb/library/azure/dn798927.aspx 
so that documents uploaded can be searched.

Which results in me adding lots of 'meta data' to the file that is being uploaded, but the actual content can have a free text search on there.

The RadCloudUpload control does not expose the necessary property when the OnClientFileUploadRemoving event fires (using Azure).

To delete a file from Azure BLOB storage you need the keyname property. At the time of the OnClientFileUploadRemoving event, the only property exposed is the orignalFileName.

Azure creates a keyname to store the file. It consists of a GUID + the original file name, e.g., for a file named "test.txt" the keyname is "554cfa68-ee24-421f-94e8-7080cf70a11f_test.txt." 

That's to allow for duplicate original file names in the container. The only way to delete a file from Azure storage is by the keyname property. That property is not exposed at the OnClientFileUploadRemoving event, so to be able to delete the file, you have to save that property in some other way at the time of uploading (in an array or database). That could fail. Obviously the control knows the keyname, as it is exposed when the file is uploaded, so it should store and expose that property.

The RadCloudUpload doesn't handle correctly situation, when the communication between client and server becomes disconnected - the client side doesn't get notified (the upload keeps spinning).
All the details and steps to reproduced are in the following thread:
http://www.telerik.com/account/support-tickets/view-ticket.aspx?threadid=951973
Thanks,
Vlad.

Ability to add Folder attribute to cloud upload control which gets appended to the SubFolderStructure in the provider. Without it all files go into the same SubFolderStructure folder, not great when thousands of files. Helps to keep the files more organised.

The CloudUpload's Progressbar is not initially shown when uploading files  in MS Edge v. 40.15063 (Creator's Edition)

When uploading a file to the CloudUpload control with an ’ apostrophe symbol in the name (Examples of the 3C’s.pdf), the control fails with 

Uncaught Error: Sys.ArgumentException: Cannot deserialize. The data does not correspond to valid JSON.
Parameter name: data
    at Function.Error.create (Telerik.Web.UI.WebResource.axd?_TSM_HiddenField_=ctl00_QsfScriptManager_TSM&compress=1&_TSM_CombinedScripts_=%3b%3bSystem.Web.Extensions%2c+Version%3d4.0.0.0%2c+Culture%3dneutral%2c+PublicKeyToken%3d31bf3856ad364e35%3aen-US%3ad28568d3-e53e-4706-928f-3765912b66ca%3aea597d4b%3ab25378d2:6)
    at Function.Error.argument (Telerik.Web.UI.WebResource.axd?_TSM_HiddenField_=ctl00_QsfScriptManager_TSM&compress=1&_TSM_CombinedScripts_=%3b%3bSystem.Web.Extensions%2c+Version%3d4.0.0.0%2c+Culture%3dneutral%2c+PublicKeyToken%3d31bf3856ad364e35%3aen-US%3ad28568d3-e53e-4706-928f-3765912b66ca%3aea597d4b%3ab25378d2:6)
    at Function.Sys.Serialization.JavaScriptSerializer.deserialize (Telerik.Web.UI.WebResource.axd?_TSM_HiddenField_=ctl00_QsfScriptManager_TSM&compress=1&_TSM_CombinedScripts_=%3b%3bSystem.Web.Extensions%2c+Version%3d4.0.0.0%2c+Culture%3dneutral%2c+PublicKeyToken%3d31bf3856ad364e35%3aen-US%3ad28568d3-e53e-4706-928f-3765912b66ca%3aea597d4b%3ab25378d2:6)
    at c.RadCloudUpload.HandlerUploader._successfulResponseStatus (RadCloudUploadScripts.js:477)
    at XMLHttpRequest.p (RadCloudUploadScripts.js:463)

Note, it's not the typical apostrophe. If you replace ’ with a normal ' windows apostrophe, the control uploads the file just fine.

In order to test, create any file on your system using that special character and try to upload that file using the demo application, located:

https://demos.telerik.com/aspnet-ajax/cloud-upload/examples/overview/defaultcs.aspx

Affects RadCloudUpload and RadAsyncUpload combined with RadProgressArea. Manifests most often on slow networks or very large files.
Scroll down for workarounds for both cases.

WORKAROUND FOR PROGRESS AREA is to round down the data, as it seems the server reports more bytes uploaded than they actually are, and that tends to happen under slow network conditions

<telerik:RadAsyncUpload RenderMode="Lightweight" runat="server" ID="RadAsyncUpload1" MultipleFileSelection="Automatic" EnableInlineProgress="false" />
<telerik:RadProgressManager runat="server" ID="RadProgressManager1" />
<telerik:RadProgressArea RenderMode="Lightweight" runat="server" ID="RadProgressArea1" OnClientProgressUpdating="OnClientProgressUpdating" />
<script>
function OnClientProgressUpdating(sender, args) {
    //debugger
    if (args._progressData.PrimaryPercent > 100) {
        args._progressData.PrimaryPercent = 100;
    }
    if (args._progressData.PrimaryValue > args._progressData.PrimaryTotal) {
        args._progressData.PrimaryValue = args._progressData.PrimaryTotal;
    }
    console.log(args.get_progressData());
}
</script>

WORKAROUND FOR CLOUD UPLOAD is to add the following script at the end of the form that will override the built-in XHR handilng to change the way the totals are calculated:

        <script>
            Telerik.Web.UI.RadCloudUpload.HandlerUploader.prototype._initializeXmlHttpRequest = function () {
                this._xhr = new XMLHttpRequest();

                var that = this,
                    module = this._module,
                    xhr = this._xhr;

                xhr.onreadystatechange = function readyStateChanged() {
                    if (xhr.readyState == 4) {
                        if (xhr.status == 200) {
                            that._successfulResponseStatus(xhr);
                        }
                        else if (xhr.status != 0) {
                            that._failedResponseStatus(xhr);
                        }
                    }
                };

                xhr.upload.onprogress = function (event) {
                    that._uploadedSize += event.loaded;

                    var percents = Math.round((event.loaded / event.total) * 100) + "%";

                    module._renderingManager.updateRowProgress(that._uploadingEntity.row, percents, true);
                };
            }
        </script>

The issue can be reproduced with a file with special foreign characters in the name like for example 2007_12_10 výkres PV doplnění chybějící části 0-HU-162345 g.pdf in the Overview demo of RadCloudUpload.