gbfromsd,
If your current version doesn't support the vav-4040, then you will definately have to upgrade. A 4040 will not show up in your system when set up as a "VAV" (4020). The latest version of ess 32 is 4.90 . Upgrading your software is simple. Just run the setup from the disk or from the setup file. To upgrade your Lingo with new firmware just perform a version download instead of a load change download. I would install everything in the default directories. This is probably the source of your errors. Finally, it is OK to Tee tap the Logic One bus, but the newer executive modules seem to be more sensitive to too much tee tapping(Lingos, etc) than the older stuff(EP2,etc).