Sorry to hear you had problems. You may not have tightened everything down, or you could have a tear in one of the couplers. This is a very simple upgrade and few (if any) things should go wrong if you take your time since it's pretty much a direct swap.
So I got tired of the OEM Evo intercooler and decided to upgrade to an aftermarket core. This is a 3" bar/plate design which has excellent cooling properties. The install is the same as before.
1. Remove the bumper
2. Remove the upper IC piping
3. Loosen the lower IC Piping
4. Remove the lower support bracket bolts (keeping the rubber donuts attached)
5. Remove the rubber donuts and carefully slide the core out.
Install is a repeat of the above.
One thing to note if this is your first time installing an intercooler, oil cooler or radiator. THE FINS ARE VERY FRAGILE. This is why they ship them with a cardboard shield. I recommend leaving the cardboard on during install to avoid raking the fins across anything while you're sliding the core into place.
a) Bumper removed. Excuse the mess.
b) Leave the donuts on until the last minute. They will support the core, but give you flexibility to move it while getting the rest of the attach points loose and off.
c) Yuck! I banish thee.....