Hello,
adding NPT, Class3A and the small UNF/UNC is simple. Because I'm from the millmeters and metric following, I simply don't know which of these - for me exotic - threads are mostly used. I've a table with #1 - #6, #8, #10 and #12, they have fixed sizes in fractions of an inch and not something like the x/2^n for the other imperial threads? Does this subgroup has a special name, because I've to make a new entry for them in the drop-down list.
And "if you leave the tables": Basically, what I do for the tolerances is converting the tables to third-order equations. For the range of the tables, I've minmized the difference between the equations and the tables to less than 1/100 mm. But I don't know how the equations behave outside. For 10% more, it should be no real difference, for a diameter 10 times the biggest one in the tables, the values are surely wrong. I did it that way to have the ability to generate threads that aren't in the tables. If you enter 216/1000 inch with 24 TPI for the #12 UNC, you get the right values, I included that range.
Do you have any data for the Acme thread?
Basically, at Newfangled they said that they don't want to change anything at Mach3 anymore, 066 is definitively the last release forever, more or less end-of-life'd it. And for Mach4, it's not a community project but that of a professional software company which simply does all the work itself and not revealing a scrap of the source code to any outsiders - or have any contributions from them. And about fooling with the macro: Basically, it wasn't programmed very clean. The macro only generates a code of G0, G1 and for the tread G32 moves and that you can change how you want. You can check that out with activating test mode, in this mode it outputs the generated code in a file. The only secret is the special threading mode, entered with two G32 concatunated to chain the retraction move to the previous G32. And that I've tested thoroughly. The threading itself as in the G32 move cannot be tampered with, that's completely internal.