Large folders with thousands of files can slow things down. Here's how to get back on track:
If Sparkle is frozen right now:
Press Command + Option + Esc to open Force Quit
Select Sparkle and quit it
Reopen and try a smaller folder (under 1,000 files works best)
To avoid freezes in the future:
Start with folders of 100–500 files
Close other apps to free up memory
Make sure you have at least 10% free disk space