Problems scrolling through PDFs is a very common issue when using RDP. I recommend you look at Ericom Blaze, a software product that accelerates AND compresses standard Microsoft RDP, so it speeds RDP while conserving bandwidth. Blaze accelerates RDP performance by as much as 10-25 times, and helps deliver higher frame rates and reduce screen freezes and choppiness.
You can read more about Blaze and download a free evaluation at:
Or view a video demo at:
Hope this helps.