Hi Jack,

we had to implement Process-Communication between a legacy FPW and a VFP-App.
We did it by a combination of DDE-Calls and (as a [necessary!] backup) a dbf-based semaphoring system, which gets repeatedly checked. In Vfp this can be easisly done via timer, in FPW it was a bit more work.

This approach would easily fit your need of "switching after button".
Process-Change via : was not needed, never thought about it.

You might check before if the poolmanager-example in VFP6 might be enough for your problems - I believe it is more stable than our kludge with DDE, but DDE is still available in VFP and avoids ActiveX-problems.

With 2 VFP-Exe's I still believe you could build upon the poolmanager- example to create an observer/mediator, which has links to both processes and thus can work without DDE and timers.

I haven't checked the eventbinding of VFP8 as of now.

We will be looking for other options after porting the legacy app to VFP6 or possibly VFP8, so pls. keep me posted [directly] of your findings.

HTH

thomas