Here is the team build we have been running through Frostmaw Dungeon in HM:
1. Ursan Tank
2. Minion Master
3. 3 2nd line damage dealers, sf eles, ss necro, fc mesmer nuker, splinter barrager ranger all work well
4. 3 healers, 1 SB prot monk, 1 HB healer, 1 N/Rt
Ursan tank:
Other than Ursan Blessing the tank needs to bring mantra of lightning with 12 points in inspiration, and Light of Deldrimore for hidden chests. If the Ursan is a Warrior bring sig of stamina to buff health.
Minion Master:
We use a JB MM most of the time and it seems to work the best.
Damage Dealers:
SF eles work well, if ss necro take barbs and mark of pain, and for splinter barrager I like the splinter/triple shot nightmare build.
Monks:
You can find a good description of how to set up the 3 healer monk/necro team in my post about my favorite monk builds.
The hardest part of this dungeon is learning the wurm spawns, and the incubus pop up parts as well. For the wurm spawns you should have atleast 2 players with pain inverter since wurm bile now triggers pain inverter the wurms are very easy now. The hard parts are the incubus groups and the mandragor groups. For the incubus groups made sure the tank has mantra of lightning on, then the HB monk should put down symbiosis and the prot monk throws everything they have on the tank. Its best if the tank stops as soon as the incubus drop and then after a few seconds the group should send the minions in to take some of the pressure off of the tank. The prot monk spams spirit bond on the tank to keep them alive (the incubus strip with a monster skill so SB will not block it), and the sf eles can glyph sac ms nuke the incubus groups. For the Mandragor groups on lvl 4 the SB monk needs to cast spell breaker on the tank and the group needs to let the mandragors fully aggro onto the tank before they move in and drop their nukes etc. This often takes 4-6 seconds so make sure you don't move in and cast too early or the mandragors will break off the tank and come back into the casters. A tank that knows the pulls and who is on vent to tell the casters/monks when to come into the aggro is the most important part of this dungeon and that just takes practice and experience. Good luck with your silverwing drops
Meiko