If you got the dialogue message like above, the ust might be slipped out of beat for some reasons.
Most likely cause is that it exists odd length notes like 481.
Originally, the Debug mode was made for just my convenience of programing, but it is useful to fix the slippage.

Two debug check boxes are in this plugin.
It displays different way, when only first box is checked, when only second box is checked and both are checked.
This cace, you can use both check way.
Checking both boxes and doing the plugin, it displays like below.


it overlapped a bit, but please ignore it.

e.g. -た / 240 / 20882/176.00

First item is the alias.
Second is note length.
Third is total length to this here.
Fourth is current tempo.

Look at the orange painted area. Rest note length is 242, and total length of '- ね' is 116402. You should fix it.