you can certainly get the door to chime without setting and unsetting, but continuously while the door is open no.
You could use a custom zone an a premier and use the warning tone and program the warning delay, so it wouldn't go off initially. Not used it in a long time and 2 minutes sits in my head as a timer value but I could be wrong.
with the Veritas, which one do you have and I'll have a think, you can use a push to set zone type and have that zone to chime, but it wouldn't be continuous and there wouldn't be a delay in sounding. (used for a door bell option), can only be used if the alarm set isn't using exit terminator.
Are you using the panels as a burglar as well as this function, I ask as that may limit the options available.
for example, you could program the veritas not to log out of engineering and stick it in a walk test, that would indeed beep if the door was left open, but there wouldn't be a delay and t would display on the keypad, only issue is someone could lo out of engineering.
There are other possibilities but would need to know how you are using the system in its entirety and then what compromises you are prepared to make.
Then it would need testing to see how close it gets you to what you want.
You could say, use a tamper zone on the veritas, and turn on the bell for the tamper and program a bell delay?
would need to be tested to confirm, the only issue would be any tamper would do the same thing.
So yes you can make the panel do things but depends on the rest of the system useage and would require testing to prove it did what you want.
I don't have the time to do that for free, even if I had more information as it would require testing on the panel and firmware you have to ensure it does work for you.