For example, here is a picture of my FMS on my flight to MDPC.

If I want to choose the custom waypoint GRAMN and press the search button, the waypoint is found.

However, if I try to choose the next waypoint, SEBIS and press the search button, it is not found.

In fact, many of the waypoints are not found, though I see they are in the database at
C:\Users\simin\AppData\Roaming\FSiPanelNavDB\NavData\ints.txt

Also there is no check for upper/lower case, so GRAMN will be found but gramn will not. Small detail, but could confuse some people.
I am using Navigraph data and I have used the Update Database button in FSiPanel to import the data.
One thing I notice is that MakeRwys generates files which are in alphabetical order, whereas Navigraph's files are in order of latitude. Perhaps that's a clue as to why some points are not found?
Regards,
Tropicflite