If You use locktite on a titanium case ( a lot softer then steel ! ) You can sometimes distroy the threads, if You loosen and tighten them to often!.
The case is that the locktite ( ALWAYS use the weakest locktite, there are 3 different ones ! ) will make the screws sitting so hard that You can get bad threads when You loosening them!
And the screws is 1,8 mm in diameter and normally the "standard" screws is 2,0 mm so YES it can be difficult to get longer screws!
I used a little locktite on the backside of the crownguard ( one of the thereads is bad ! ) and that keeps it in place but then it will be a little bit more difficult to take it away again!
On the steel version I think it is a little easier to tighten the screws with locktite but use only a little!
If the screws really HAS the CORRECT lenght then there should be no problems with tighten them!
Hope this helps !