I am very new to the CNG scene/

I just bought a 98 ford contour 169k miles, bi fuel. Owned by school district, ran on CNG 90%, of time. Drove from Phenix to Salt Lake, performed very well.

My questions...
1. What do I need to keep an eye on, with this specific vehicles and miles?

2. How do I maintain a CNG vehicle, specifically this one?

I told you I was new!!