I have received renders named sequentially in this way.
Hitfilm doesn't import these files in correct order.
Its not following the normal way which is to add a zero before single digit numbers like *_01.png. Other appz have no problem
When the sequence reaches 100 or 1000 frames the names are now *_100.png
hitfilm has trouble making sense of it because the number of digits is not the same. Other appz have no problem.
I could rename it to follow typical conventions like *_0100.png but if other appz have no problem I think its a hitfilm issue.