Hi SamCodes,
Just in case you are not aware, there is an additional Official Practice Question pack you can purchase from mba.com. It sells for $29.99 for 100+ questions, kinda expensive. But those are official questions.
Also, if your weakness is in G&T, I think you can try practicing more questions from the DI forum. Filter questions for the following two groups of sources:
1. GMAT Prep(Classic) & EA - those are official questions.
2. Reputable Prep companies, such as Manhattan, Veritas, Kaplan, etc. I personally feel that G&T questions are less sensitive to non-official question, unlike MSR or TPA. So 3rd-party questions might be acceptable.
SamCodes
3. Also, what other sources can be used to practice questions for DI other than OG materials? Will it help to refer the previous years OG materials?