My problem is that when is changed size window or is changed colour of object, it stop to work, not immediately but after short time drawing, I don't have idea where I work with memory or something like this what is responsible for this problem.
If you have some idea, I will be happy.
Thank you
Here is link there is code and exe folder.

The link you gave is some sort of download page written in some language I don't know.

attach your project to your post here at DaniWeb. Just use WinZip to zip it up, press the Go Advance button in the "Quick Reply To Thread", then the "Manage Attachments" button.

This will not guarantee you will get the answer you want, but at least some people might bother to look at your project.