I already answered your support thread and for your convenience and for others who might need this information I pasted it below:
I am afraid I could not completely understand what exactly you mean by "My Radslider control is limited to 10 slides" - do you mean ticks, or items, or slider instances or another thing?
If you want to have more ticks you should configure the slider according to this demo:
E.g, the following code will show 25 ticks:
If you meant items, you should simply add the desired number of items in the Items collection.
As to slider instances, there is no limitation of their number on a sample page.
I hope that my reply is helpful, in case you need further assistance, please provide more detailed explanations, sample code and a screenshot with the very same code with the problem clearly marked and I will do my best to help.
the Telerik team
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