M.O.T.: Directway-Timbuktu combo info help needed

[Russell McGaha]

I need some help learning what questions to ask, to get the help/info I 
need.
Background:
	I recently had DirectWay Sat. Broadband installed [I live in an area 
where 28.8 in the Highest Possible Dial-up connection], while waiting 
for my billing info to go thru, so I could set up my e-mail accounts, I 
used timbuktu to check on two of my three Mac's at work.  The 
connection was good and everything was alright.  Later, after I got my 
billing info and e-mails setup correctly, I tried to connect to my two 
Mac's again and could not; I figured it was a transient problem and 
went on.  I tried again later and still could not connect, so just out 
of curiosity I tried my other Mac, connected with no trouble, I again 
tried the other two with no success.  The next day I called tech 
support to see what the problem was and they said it was nothing they 
were doing; I find this strange, since I can timbuktu into the one but 
not the other two, [the tree machines are almost identical for this 
purpose] and I can still timbuktu into them [all] if I go back to my 
dial-up.
Question:
	Can anyone tell what I can do in the way of diagnostics [with 
directions] to find out what is going on and why.  During the day I 
have full access to all three Mac's, and can get access to the Router 
which we're behind [TCI Deltacom fractional T1 connection] at work.

With DEEP appreciation for ANY help provided.

Russell McGaha
PS Sorry for the cross post; I wanted to reach as wide an audience as 
possible.