Import externally edited mxliff back in Studio: how to prepare correctly

Hello everyone,

I thought I would have a good workflow by translating the first of two mxliff files (they have about 40% reps and matches) in Studio, upload it back to Memsource, have it reviewed, accept or reject the edits and download that file ("ED" extension in the file name by default in Memsource), open that file back in Studio and confirm all segments.

I now realize I made a mistake by not adjusting the batch task when preparing this edited file for Studio. All the edits were overwritten by my existing TM. I have a workaround for now by creating a new TM and disabling any other ones. The mxliff file opens in Studio in review mode and has the corrected content. After confirming all segments, I have a TM to use for the second file.

What settings should I have used in order to overwrite existing TM matches and apply the edited content to my tm's?
There is now also probably a best way to prepare/pretranslate the second file first and confirm and lock all 100% matches using the new TM only and after that enabling my other TM's? I have never done this before. If anyone can point me in the right direction, that would be great.

Thanks.

Update: With what I did as described above and leaving the existing batch settings as they are, I do at least have a 53% pretranslated file with confirmed 100% matches and can go from there. I need to make sure that none of these will be overwritten by existing tm's that might somehow be recognized as "better". Is locking these segments the best way to do this? Any other settings I should change?