FOA has color code guides you can print yourself or download to your smartphone or tablet.See https://foa.org/tech/ColCodes.htm

What is included in grants depends on the project submission. A "middle mile" project could include the fiber optic cable plant with drops for users to connect to dark fibers or be a complete communication system with carrier Ethernet service points to users to connect. In either case, it includes all the construction, cable plant installation and testing. A communications system proposal could also include connecting users if the originator of the proposal knew the number of users to be connected -each one of which adds costs. Same for a FTTH network. It could just be the cable plant, a functioning PON system with drops available to all users passed or include connecting users. One could do an educated guess on the percentage of homes passed that would connect, or include a user paid connection fee to cover the costs. It depends on the proposal that was submitted and approved.

Those are the two wavelengths used with singlemode fiber. They are used because they were two wavelengths that the fiber would be singlemode (>1270nm) and wavelengths that it was easy to make solid state lasers 40 years ago when they were introduced. Longer wavelengths like 1550nm have lower loss in the fibers so the fibers for very long distance links are optimized for 1550nm

The loss can be connections, including dirty connections, bad splices, damaged cables, even a bad splitter. Have you tested with a high resolution OTDR?

Among the most established ones here in US are ArcGIS, IQGeo, 3-GIS, Vetro and OZmap. All seem to have proponents but we do not have much practical experience except one of the FOA Tech Advisors uses OZ map.