The data written to IUNIt in VERBose mode is just a long list of the start and end times, with identitites of the involved atoms/groups, of all hbond/contact/bridge events.
Note that the default criteria to define a hydrogen bond (r(H-A)< 2.4A and no angle cutoff) are perfectly fine (JACS 114:4028). The COOR HBONd command is not particularly fond of keywords NCUTA and NCUTB (very few commands/keywords in CHARMM are identical in the first 4 positions).
SKIP 5 is very frequent sampling...
Note also that the .AND. operation has higher priority than .OR., so this selection may not do what you want:
select segid proa .and. type HN .or. type O end
For COOR CONTact you probably want a longer cutoff than what is used for hydrogen bonds.