Mydumset is in Reaper Plugins folder. And i select Insert new track and after that i select Insert new virtual instrument on new track and select mydrumset, but then comes error and then comes this text:

Runtime error

Program G:\Musiikki\REAPER\reaper.exe

This application has request the Runtime to terminate it in an unusual way.
Please contact the application's support team for more information.

What is the problem?

I have 2,0 GHz AMD Sempron processor
2 Mb memory
Windows Vista

Hi.
It seems like this is a reaper question and I'd advice you to try reaper forum or contact some of the Mydrumset users with a PM on this forum.