Ok well you are only using one product, the shampoo conditioner! I have used that in the past and it is "ok". White bottle green writing right? You wouldn't experiance the chalky marks unless you'd used the paint restorer or SRP/UDS products.
I have the full range of AG and the SRP and Ultra Deep Shine DO leave white chalky residue over any vinyl or rubber parts which are a right pain to get off. From reading up about their range, they use chalk fillers to colour the liquids which dry and cause a problem.
Meguairs range is a far better product, try their gold class shampoo, nxt tech wax, hot wheels wheel cleaner, and then tell me you still prefer AG
I'll be more specific next time for you Steve78

Whats wrong with turtlewax?