When you run CTM 178 from console you can compact the snapshots and it works (if you start it from GUI it has a bug on defragmenting snapshots earlier in time).
It compacts all the snapshots.
But the progress bar goes one by one until 21-22% and then jumps to 100%.
The “current snapshot” works until 100% (optimizing).
But the others don’t.
Hi Tech:
Thanks for your feedback.
We will improve it in the next version 
Best Regards.
Ok. Thanks for listening 
It was not completely solved in version 187 Beta.
Now the progress bar goes until 78% and then jumps to 100%.
The “current snapshot” works until 100% (optimizing).
But the others don’t.