how do I know how many times to twist the dacron string? It should not be strung without a twist, correct?
A few twists at least. You may have to add several to get the brace height high enough. Factory strings are usually "one size fits all"--and usually doesn't fit properly at all.
Additions like a stabilizer are a personal thing. I like to add as little as possible myself, as one of the main reasons I switched to traditional was because of gadgets getting loose, breaking, etc.