<<You might try your run line as follows:
RUN TTEST;XL='XL.PUB.SYS,XL.PUB,XL.PUB.SYS'

Since load time resolution of externals is not recursive, meaning
external resolution is only one way, left to right, your example had
procedures in 'XL.PUB' not finding stuff they needed in 'XL.PUB.SYS'.  By
repeating 'XL.PUB.SYS' again they can be found.>>


Say what? MPE doesn't allow repeats in the "XL=" string.

[1] STEVED.ECS:run exdatec;xl="xl.ecs.mk50,xl.ecs.mk50,xl.pub.sys"
DUPLICATE FILE IN LIBRARY LIST.  (LDRERR 600)
Unable to load program to be run. (CIERR 625)

and also appears to have rules about where XL.PUB.SYS can appear in the
string:

[1] STEVED.ECS:run exdatec;xl='xl.pub.sys,xl.ecs.mk50,xl.pub.sys'
A subsystem library binding error occurred (XL.PUB.SYS not followed by
NL.PUB.SYS).
Native mode loader message 504
Unable to load program to be run. (CIERR 625)

Steve