Hi Infel
thx to your tip with resolution I found the solution for this issue. Client doesn't work when you are using custom DPI(text size) larger than standard 100% on Win7. That's why client window was croped, I was using 125% medium DPI size. Here is how it looks when it's back on standard 100%
after changing it back to 100%, error pop ups are gone when switching to telemetry tab as well as I'm able to get 'race start' message now. You can change your DPI on your desktop and try it out. So I guess client was working all along from the beginning, it's just having some issue with custom DPIs. Thanks for the help