Enter #INTERVAL xxx directives to set the exposure intervals. You can insert these before each target if you want different exposure intervals for each target. Each time ACP sees #INTERVAL, it will use that interval for all targets following it. Use the magnitude of the object to estimate a good long exposure for each target.
You should have something like this (in this example, PGC galaxies were used). Note the various formats that can be used for the coordinates (and that the spaces between parts are TAB characters). You can just use one format:
#interval 120
#FILTER Luminance ; Required for systems with filters (carries over across targets)
PGC22857 08h 08m 41.60s -18°41'38.0"
PGC3173 00:53:58.00 +00 59 16.0
#INTERVAL 90
PGC3291 00 55 44.50 +00:38:17.0
#INTERVAL 180
PGC29822 10.2307778 38.7652778
PGC21739 7.7657778 -2.9111111