No, RAD PDF does not have a fixed limit for the size or page count of PDF files it can load.
The limits in place for PDFescape are in place to help reduce server load and abuse (as PDFescape allows anyone to open a PDF file in its RAD PDF instance).
As RAD PDF installs on your own server, you are welcome to set your own limits (or none at all).
By default, RAD PDF does not limit the size or number of pages for a document it can load. The size of a PDF can be checked prior to a document being loaded. The page count of loaded PDF files can be limited using the MaxPdfPages property.