Project autosaving will be implemented in Radialix 3.
Radialix 3 developer package with project autosaving can be downloaded here (temporary link):
radialix.ru/ru/files2/Radialix_3.00.00.202.exe
This installation package contains both 32 and 64-bit editions.
WARNING: Radialix 3 is being developed right now. This is not ready-to-use product nor it's release candidate. Do not use it in your real projects.