After the feathering bug is fixed it's likely that a free licensing period will be granted. Takes time.
Wait for the green line to complete; seeking and playback should be smooth. Using version 11.22, with a one-hundred-minute clip on the sequence, after fully caching there was no re-caching when the timeline was expanded or contracted. As for 'skipping' - allow VP a few seconds to re-cache after making changes, such as adding effects.
Hardware capabilities, project complexity and length all affect caching. You don't specify the other issues in 10.21. Quirks often turn out to be user unfamiliarity.
Unlike some other NLE software that is either sold strictly via subscription or is updated yearly for a fee, and maybe with a major patch, frequent Videopad releases incorporate performance enhancements and feature improvements. Considering that rapid upgrade cycle, something may have broken and not been spotted during beta testing. Like the feathering issue. it may be months before a user encounters it. Once confirmed, the fix is usually quick.
If you visit other company's forums you may see reports of bugs that don't get fixed until a major patch or new version arrives.
