In the Catachan Codex Rough Terrain Modifications allows their Sentinels to re-roll their movement dice for rough terrain. Would this also be true for regular Sentinels too?
Yes, it would.
Jump pack troops and bikes die on a roll of 1 on a D6 if they move into difficult terrain. Does this still trigger a booby trap?
Yes, it does.
If you use Deathworld Veteran Snipers in a normal Imperial Guard army, if the mission allows infiltrators to use a free movement before the game starts, can the Snipers use that movement?
No.
Also, if the Snipers are held in Reserve can they just be placed on the table edge and never moved, or can they not be brought on at all?
Snipers held in reserve may not be used.
Does the special ability of Colonel 'Iron Hand' Straken, Catachan Devil Force, entitle his force to more than the 0-1 Catachan Devils squads, or does he still only get the one but can take it as a Troops selection.
He can have any number of Catachan Devils squads.
Do the heavy flamer weapons teams have one heavy flamer and one normal guy or can you get 2 heavy flamers. The confusion stems from the Catachan vs Dark Eldar battle report where a Veteran Assault team had 2 heavy flamers in the unit. The Codex seems to be clear that you get the weapon just like any other ‘team’ weapon (with a gunner and a loader) but the heavy flamer models have no loader and are packaged 2 heavy flamers to a blister.
The WD team wrote up the army list incorrectly (the squad only had one heavy flamer). The Codex is correct, just ignore the WD list.
If a Catachan Sniper is subject to Tank Shock (assuming the tank passed the Difficult Terrain test), how would you resolve it?
Now, that is a rhetorical question! Roll a D6 for it I guess, 1-3 he gets squashed, 4-6 he doesn't, but I really don't believe this has actually come up in play.