It's not in the common, hacking, autosoft or simsense categories - which categories of options should it get?

I thought Common. I can't confirm this yet, but it's my understanding that all programs got common options and then had other options added and removed (such as combat etc).

Ignore the categories that the program options are grouped into - those don't matter. What matters is the categories listed on each individual program option - those are the categories of programs can select that specific program option.

Of course that's also easy to house rule - on the copy of Tac Net Software you've already made, it's simply a matter of checking the "Allows Modifications" checkbox, and then in the "Program Options Allowed" option immediately below that, choose "Common Use Program Options", "Common Use Program Viruses", and "Common Use Program Bugs".

Any way to limit the rating as a CF? It's limited fine as a program but as a CF it will go up to 6

Press the "Fields" button at the top right, and add new field values. The first is Field Id: trtNatMax, the second will be trtMaximum. Set both to the same value. (capitalization matters for the field Ids).