Hey. So here's a somewhat major update and bug-fix version of the X-Emitter V1.10.1 dealing with scene changes.
This is a bugfix version on top of another new version, X-Emitter V1.10, which added particle prototyping as a potential speed-up (only in the Generic XParticle script). Particle prototyping is where the first particle is used as a 'base' for what the other particles do. Once that particle has finished its course, other particles copy its properties and live 'its life' as well. While the other particles can't be randomly colored or be as unique, there can be a speed-up, depending on different factors. Another emitter has been added to the demo blend to showcase this.
As for the bugfix, I found out while using X-Emitter that when scenes change, the particles stick around in the scene list, and so basically are referencing non-existent particles. The fix for this is that the calculator object clears out the particle list when it's created. So, just have ONE particle calculator per scene, and ensure that it runs before any other particle script, as the example blends show. If you don't it won't work well with particle prototyping, as the first particle will be ignored.
The second simple example scene goes back to the complex scene to show the error should be fixed. :) If the error persists, please contact me either here on the comments, on the BlenderArtists forum, or by e-mail at firstname.lastname@example.org.
Download X-Emitter V1.10.1 from one of the mirrors below.
Mirror 1 : MediaFire
Mirror 2 : FreeDrive
P.S. If I recall, FreeDrive might delete the file if it's unused for too long, so if it is, tell me and I'll re-upload it.