Intermittent forms errors related to Hint.PLL (part one)

Note: there are really two problems here & I am looking for answers to the both questions...(hence the whopping points) but may give full points to someone who helps fix only the first.

We are experiencing some intermittent errors on two of our Oracle Forms modules which seem to be caused by calls to procedures in the Oracle Forms HINT library.  The two cases seem to be related, so I have grouped them together, but they are occurring on two different form modules.

Form A:

When the form initially opens, these error messages appear, at least 50% of the time:

FRM-41045: Cannot find item: invalid ID  (appears 3 times, and is sometimes followed by:)
FRM-41058: No such property for Get-Item-Property (which may appear by itself, or after the first messages)

These error messages are intermittent, apparently originating from within the attached Oracle HINT library, from the procedure HINT.ShowButtonHelpHandler, called from the form-level When-Timer-Expired trigger, which seems to fire on a fairly random basis in relation to when the form is initially called from the menu. (well at least it seems random)
      
The problem can be "fixed" by commenting out the call to the HINT procedure in the When-Timer-Expired  trigger, which is the only place it appears in the form.  The drawback is that the "balloon-help" hint text no longer appears.  With or without this fix, the business functionality of the form works exactly the same...just not as polished.

We have tried the following to fix the form:
1) run the form in debug mode
2) inserted my own messages: messages seem to affect the time of the initial appearance of the defect - an unreliable testing method
3) examined the code involved in form level triggers which fire before the messages appear (i.e.. code called from the Pre-Form or When-New-Form-Instance triggers).  There were no apparent anomalies.
4) created a local copy of the procedures in the Oracle HINT library, specifically, a copy of the HINT package and       package spec.  We won't modify this library itself, as we cannot predict how it will affect the other modules.  I placed messages in it too, in the hope of finding the cause of the error.  This is high-level code, and the results of this testing were inconclusive, as I don't precisely know what I should be looking for.

(now..the related question..but answer should be posted in part two)

Form B:  

This defect is also intermittent, and seems to stem from an unhandled exception which is being raised by the form-level When-Mouse-Enter trigger.  The form opens in ENTER-QUERY mode.  We EXECUTE-QUERY on any record in the topmost block, and wait a few seconds for all of the several master-detail relations to do their work and populate the other blocks on the form.  Upon placing the cursor over a button in the last block on the screen, which calls a popup block for data entry, the message FRM-40735 When-Mouse-Enter trigger raised unhandled exception Value-Error appears.  After it has appeared once, the same message will continue to appear whenever the mouse is moved.

Additional Information:
1) Moving the mouse before the form has finished populating all the blocks and then navigating to the last record of the last block on the form seems to precipitate the problem.
2) Although the application files are all kept on our LAN, the database is at the client site, and our connection is often SLOW.
3) We are using Pentium 133 workstations, Windows NT 4.0, Oracle Developer/2000 toolset (32-bit version - the version of Forms is 4.5.7.1.6) running against an Oracle7 Server 7.3.2.3.1 (with the distributed, replication and parallel query options).
      
Any help or advice you can offer would be appreciated.  Please let us know if you need more info.  Thanks.

JTrifts