Exhaust popping - Did it do this prior to miltek being fitted? Does it smell like it running rich? Could be a fueling issue so maybe maf but get it plugged in first. I had a 3" custom exhuast with decat mine popped every so often so thats pretty much normal by sounds of it.
Slight judder - Depends what you by this, does it judder everytime or only when cold? Could be dual mass flywheel issue or does it have a solid flywheel conversion?
Revving high - It shouldnt rev upto 2k and need assisting to get back down, when cold it should go just above 1k then drop to around 800-900rpm.
Clean the TB this should help sort the rev issue.
I would never advise anyone to drive any car turbo, NA or charged to start a car and drive it straight away, You should atleast leave the car idle at normal rpm's before setting off and never boost the car until its upto temp. You will be surprised how something this little keeps everything happy for your engine includin the little turbo.
