Root Help needed with rooting/custom rom



Can anyone help me! I'm banging my head now :)

I've a htc hero, i'm on my 2nd one due to build issues with the first. I managed to root the 1st no problem and run custom roms... but this 2nd one is a real biatch to do.. the build No. is 2.73.405.5 which I guess is a unbranded HTC rom it came installed with. The problem is when I try to start down the rooting path by trying to install the FlashRec.apk 1.4 version I get the error "Parse Error, there is a problem parsing the package" This is using Linda or Astra..

Can anyone help past this 1st step??