macOS version: 10.15.3 (19D76)
Kap version: 3.1.0
I'm not able to reproduce with a 2560 x 1440 29:18:75 long capture exported as MP4 at 60 FPS. The export is resource intensive and runs for several minutes, but progresses as expected:

How does your export window look while exporting @ngeshlew?
Hey @skllcrn , you showed me a workaround on twitter:
You might still have the original video recording open in one of the Kap windows, if not, see if you can find it in the export history window. From there, cancel the stuck export and open the original recording again.
Then use the File menu in the menubar and save the original recording
It sounds like you may be converting a very large file to GIF, which is extremely resource intensive
With the original recording file handy, you can open it in Kap again if you wish to export with other settings
and it worked. Thanks!
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Hey @skllcrn , you showed me a workaround on twitter:
and it worked. Thanks!