Also happened to me this morning. I gave-in and paid for the upgrade since I've been a happy Sublime user since inception. However, I am very disappointed in the overall performance compared to ST3. Indenting code via TAB takes approx. 500-850ms and is a noticeable delay that would annoy just about anyone. Overall it's a bit shocking. It seems like the creator could've been short on dough and came up with this dark s…
If you have any plug-ins installed, try uninstalling/re-installing to see if one of them might be the culprit. What you're describing isn't normal behavior.
1. I store my project/workspace files under ST's root installation folder and the upgrade DELETED them all
2. I'm running ST on Win10 and after the upgrade, ST4 is now installed under "C:\Program Files\Sublime Text 3". You would think that there'd be a post-install script to check executable path for 3 and change it to 4.