Hi. I can't say I know much about the technical aspects of AE (...I have used it for many years, but I'm not an official tech guy... just another user using the forums today).
Hopefully someone who knows will give you a response, but I just wanted to let you know that since upgrading to AE7 I too have received that error on several occasions, including a seemingly bogus one for audio saying that I need 'at least 2 frames' or something.
AE7 seems to have a memory leak issue (among other issues). Certainly not the most stable.... AE6 was really bad for that, and AE5.5 (which I have been using for most of my career) was seemingly more stable than either AE6 or AE7.
As annoying as it is, it's generally (I think) just AE randomly getting tripped up, and is most likely not a 'permanent' thing (either to your current project, or AE itself). Try Purging (in the Edit pulldown?), which clears the buffers and sometimes helps... otherwise just restart it, and it should be okay.
Sorry I can't give you specific help on that, but I thought I'd tell you what I know until someone else shows up.
Yes and no. These issues are mostly related to your system schuffling resources around and then not refresshing them for a while. I know it's annoying and confusing, but it mostly has to do with Adobe using different UI libraries ever since AE7. I haven't really come up with a scheme to this, but it mostly seems to hinge on the amount of VideoRAM your graphics card has. For the time being, you should minimize AE to the taskbar during renders. In an odd way this helps to prevent such problems as it enforces a regfresh whenever you maximize the window again. You can also try and play around with your graphics card settings. I know for certain that on one of my systems using a different OpenGL setting on the NVidia settings brought betterment.
I"ve got the same problem here since about 1 month. It seems that for us, this "Unspecified drawing error" is linked to the remote access to the render servers computers. There is a "redrawing" of the display that is causing that error...We have change our remote display settings, took off
the savescreener and put all the machines on the sames displays settings (and on the remote acces display settings)...It is doiing it less often....But still, it is doiing it. It appears that the error appens when we shut the remote connection...Not when we log in to it. But when we log off. Right now I don"t know what to try.
For now...We have disable remote acces...ANd there is no more drawing errors. But we would like to be able to use it without stoping the after effects renders in the future. I"m thinking that maibe with cs3 we are gonna be able to use remote without having this problem...But it is not sure at all....
I can't say much about remote administrating AE, but it should be no different than running it locally - the RDP agent will only compress the data stream after the screen buffer has been fully drawn. Are you using Windows' own Client? Which combination of operating systems do you use? You might consider trying an alternate tool such as Citrix, VNC or VMWare server. Perhaps this will be better suited for your needs...