Do you have a copy of the Navtech(aerad) chart for this place?Does it mention anything about the approach not being available at night?
Yes...
It says: ''Note: When VGSI inop, procedure NA at night. Circling NA'' and the note was revised Dec 2012.
It also gives a 3.3deg slope on the profile chart but a 3.2deg one on the DME vs. ALT box; probably rounding either way.
There are CAT D minima of 1200' and 1 & 5/8sm for the LOC+IMTOY and 1380' and 2sm for just the LOC. Out of interest, the RNAV (GPS) 18 has 1200' and 1 & 3/4sm.