Multiple time signatures in midi file generally don't import correctly, but occasionally have done?

HI.
Thanks for this amazing software. I love it!
However I have a problem and I wonder if you can help me solve it.
I have a midi drum file that I exported from Cubase.
Most of the time, when importing it, it comes in with a time signature of 3/4 at the start and no other mention of time signatures throughout.
But once or twice it arrived with all of the time signatures that are supposed to be there (the original is filled with many different time signatures).
The work involved in putting them all in is overwhelming.
As such I'd really like it if I could figure out how to make musescore always import the midi file with all the time signatures in place.
Do you have any suggestions?
I have attached the midi file for your reference.
I've also attached a screenshot of the tempo track editor from Cubase so you can see that I have built in time signatures in there.
I'm using Musescore version 3.4.2.9788.
I'm using Cubase Elements 10.5.12
Thank you so much.
Martyn