I have downloaded, installed, registered, paid somewhat 40€ and here is my comment:

- numeric bugs:
converts 75 to 7500, 75000 and 0.75, depending how many dots and/or commas you have added. even entering no seperator yields in irratic number behavoir (open prefs: enter value, close, reopen: new random value, close, open: another new random value)

- no support:
Author refuses to anser email, support requests, does not allow forum usage (im wainting for my admin aproval about 3 weeks now)

-inadequate workaround:
i found a woirkaround in FAQ recommending to set my system to english. bug persists, all applications gone mad, Timenet still can't calculate 1 hour x 150 € to 150 € billing

Resume:

HANDS OFF if you are non-US