Hi,
I came across with a rendering bug,
to reproduce it copy the following two lines and paste them into a TM document:
587 3 402 ̃ wa:w.4 NULL NULL NULL NULL 591 3 402 kha:ŋ.4 kha:w.4 NULL NULL NULL NULL
On my machine OSX 10.9.1 TM 2.0-alpha.9503 these lines are rendered as shown in that picture:
The "problem" seems to be that TM is not able to get rid of a TAB {utf8: 09} (and I believe this's true for each CONTROL character) followed by a combing diacritic - in that case a combining tilde {utf8: CC 83}. The actual data in the TM window are correct, you can e.g. look for TAB characters. If you remove the combining tilde TM renders the text correctly.
I'm aware that this is actually my fault since a combining character shouldn't appear after a control character and "more actually" I'm glad that TM had this bug thus I could find my fault ;) but I think TM should do it like other Mac apps e.g. TextEdit.
For safety reasons I attached a UTF-8 text file containing both lines.
Cheers, Hans