2.2.1.19 was the final non-subscription version.... so anything after that (I believe version 3) was subscription only. We are still running the final non-subscription version today. It does have its quirks and a few bugs but nothing terrible. At one point Mark the owner emailed me a .lic license file to make reinstall easier. With that, you install, let it open, then close it back down, copy the .lic file to the \ProgramData\Estimate\ folder and when you open it again its licensed.
If you currently have version 2, check for a .lic file in that folder and save it. That might let allow you to reinstall and bypass registration.
The actual instructions from Mark were
"1. Close EstiMate and drag the attachment from this email to the desktop.
2. Click your Windows "Start" button, click Search and in the search field type in "C:\ProgramData\EstiMate" (without the quotes), and press "Enter".
3. This will open up a window for the EstiMate folder. Drag the license file you saved to your desktop into this window, and drop it in any blank spot.
4. Now close this window and restart EstiMate."