I agree that the traps were too obvious. I played it essentially as written, but got around that in two ways. First, when they opened the doors, they saw a semi-fresh dead body of an adventurer on the floor and Splug (who had been with them, but ran away two encounters previous) was looting the body. Splug was surprised to see the PCs and ran to the other exit (recall that the traps do not affect evil creatures). So, one of the PCs ran after him... right into the big statue trap. Second item was that once the trap was sprung, the door magically shut (despite them knocking it off the hinges previously), locking one in the room and the rest still in the hallway. That bothered them quite a bit, and they were quite eager to get into the room and attack the trap that was attacking their party member.
However, they saw the traps of the dragon statues and the water trap a mile away, so they just blasted them from afar.
Nice move with Splug, my players didn't even want to let him go- Dirty was all for killing him, he's a 'no prisoners' kinda Dwarf, in previous outings in KOTS I've got good mileage out of Splug. These guys however are like 'Dungeon Auditors'- Grey is mapping the place, and every exit and/or passage has to be checked, and the further they go in, the more calm (and in cases over-confident) they seem to get.
The traps were all too obvious though, although I guess it depends on the ages of the players, younger members of the community may prefer to 'go see' rather than blast from range.
More of the same follows...
H1 Keep on the Shadowfell
Encounter #22 Area 17: Ghoul Warren.
The PCs saunter on, another pair of doors, which Winstanley approaches and peeks through- Zombies.

Dirty grins, spits on his hands, hefts his Vicious Maul and kicks the doors in- 'it's clobbering time!” he declares, losing the Surprise Round in the process.
Over-confidence and/or a healthy disrespect for Zombies- a bit of both really.
Good Guys
Dirty Biskit, Male Dwarven Fighter 3 (HP43)
Kaspard, Female Half-Elf Cleric of Bahamut 3 (HP35)
Winstanley Portico, Male Halfling Rogue 3 (HP35)
Grey Morlock, Male Human Wizard 3 (HP31)
Phrenic, Male Tiefling Warlord 3 (HP34)
Bad Guys 1031XP Level 5 Encounter.
Zombie Rotters Level 3 Minion [ZR] (x12) (HP1)
Clay Scout Level 2 Lurker [CS] (HP31)
Zombie Level 2 Brute [Z] (x2) (HP40)
Ghoul Level 5 Soldier [Ghoul] (HP63)
Initiative 29 Grey 27 Winstanley 23 Ghoul 22 Phrenic 19 Kaspard 13 Clay Scout 8 Zombies 7 Dirty 2 Zombie Rotters.
Round #1.
Grey- Move. Scorching Burst Z1 & ZR2; Hit both ZR2 6 Fire damage- DEAD & Z1 6 Fire damage (34 HP).
Winstanley- First Strike Sly Flourish Combat Advantage Z1; Crit 27 damage (7 HP bloodied).
Ghoul- Move. Charge Phrenic; Hit 8 damage (24 HP) & Immobilised.
Phrenic- Immobilised. Steel Monsoon Ghoul; Miss. Save vs Immobilised- Fail.
Kaspard- Move. Turn Undead Ghoul & ZR1&3; Hit ZR1&3 9 Radiant damage- both DEAD & Miss Ghoul 4 Radiant damage +5 (Vulnerable) = 9 damage (54 HP).
CS- Move. Mind Touch Kaspard; Hit 4 Psychic damage (31 HP) & Dazed & Clay Scout Invisible to Kaspard.
Z1- Move. Slam Kaspard; Miss.
Z2- Double Move- lurching towards PCs.
Dirty- Shift. Crushing Blow Ghoul; Crit 38 damage (16 HP bloodied). Action Point- Tactical Presence/Assault from Phrenic +2 To Hit & +4. Reaping Strike Ghoul; Miss 7 damage (9 HP bloodied).
ZR1- DEAD.
ZR2- DEAD.
ZR3- DEAD.
ZR4- Move. Charge Kaspard; Hit 5 damage (26 HP).
ZR5- Move. Charge Dirty; Miss.
ZR6- Double Move close in on PCs.
ZR7- Move. Charge Dirty; Miss.
ZR8- Double Move close in on PCs.
ZR9- Double Move close in on PCs.
ZR10- Move; Charge Kaspard. AoO Dirty; Miss. Charge Kaspard; Hit 5 damage (21 HP).
ZR11- Double Move close in on PCs.
ZR12- Double Move close in on PCs.
Time to play 20 minutes including set up map and minis.
End of Round-
Good Guys
Dirty Biskit, Male Dwarven Fighter 3 (HP43)
Kaspard, Female Half-Elf Cleric of Bahamut 3 (HP21/35)
Winstanley Portico, Male Halfling Rogue 3 (HP35)
Grey Morlock, Male Human Wizard 3 (HP31)
Phrenic, Male Tiefling Warlord 3 (HP24/34)
Bad Guys 1031XP Level 5 Encounter.
Zombie Rotters Level 3 Minion [ZR] (x12) (HP1) 3 DEAD.
Clay Scout Level 2 Lurker [CS] (HP31)
Zombie Level 2 Brute [Z] (x2) (HP7/40 & 40/40)
Ghoul Level 5 Soldier [Ghoul] (HP9/63)
Action Points 1 Total 1
Daily Powers 0 Total 0
Healing Surges 0 Total 0
2nd Winds 0 Total 0
Crits 2 Total 2
PCs Ko'd 0 Total 0
Comment: And my Ghoul is buggered in the first turn of play, damn them!