AppleTalk / Interrupts / ProDOS 8 / DOS 3.3 Launcher

[johnmac@fawlty.towers.oz.au (John MacLean)]

I have been trying for some time to get DOS 3.3 Launcher to work
over an AppleShare network, but I'm having problems which I believe
are caused by incorrect handling of Appletalk interrupts.
I am therefore looking for help:

BACKGROUND QUESTIONS:
1) When running ProDOS 8 and making use of shared file systems (off a Mac
server), does anyone have anything to say about interrupt handling?

2) Should interrupts be enabled when ProDOS calls are made?
Does the answer to the last question change if the ProDOS calls are
accessing an Appleshare file server?

3) Must I have interrupts enabled almost all the time?
If the answer to the last question is yes, what is the longest time
they can be disabled without causing problems?

THE MAIN QUESTION:
I have a rather unique situation in which I need to swap out the
memory occupied by the ProDOS 8 MLI.
Would it be possible to patch an interrupt vector (either in page 3
of bank 0, or in bank E1/E0 on a GS) to handle the interrupts
generated by Appletalk without having the MLI in memory?
ProDOS is still in the language card, if this is any help.

Any help on this would be greatly appreciated....

John MacLean.
-- 
Email:    johnmac@fawlty.towers.oz.au                   Phone: +61 2 427 2999
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