Zib:
On a second review of the plugin code, you probably don't have a single object that hass all those vertices. Rather, it is the combination of several object's vertices into one plBufferGroup that is exceeding the count.
Currently, the plugin does output the number of vertices per object. Look in the log output for the following:
exporting ObjectName NumVerts vertexs, please wait several minutes
This will tell you how many vertices that object ObjectName has.
To see how these objects are grouped together into plBufferGroups, add the following line to alcdraw.py, in plDrawableSpans.export_object() [line 1048]:
vstart=len(bufferGroup.VertexStorage)
print "##### Found buffer group %i which currently has %i verts" %(sliceid,vstart)
vstop=vstart + len(vertexs) #wrong!!! - don't trust it
[Note: I marked the line in bold that you will insert.]
Even though there is apparently a safeguard to prevent adding too many vertices to a plBufferGroup (see plDrawableSpans.find_buffer_group()), it doesn't seem to be working. That will need to be fixed.
Here's a workaround for you in the meantime: put some of the objects into a new page. Each page gets one drawable span (and a set of plBufferGroups).