I put a little more work into running Zotero on Plasma Active tablets. First of all, it is now possible to install Zotero via zypper. You can get Zotero from my xulrunner branch repository on Mer OBS. Furthermore, it now comes with a .desktop file; so, you can start Zotero like any other application.
Another improvement is that the font size, even in the menus is bigger now. For this, I added quite a hack to xulrunner; you can find the according patch also in the project on Mer OBS. Unfortunately, there are still issues with respect to rendering the menus but at least they are now shown at the correct positions; one does not have to guess the position of items anymore.
Additionally, I upscaled the smaller icons to 32×32 which seems to be a good size at least for Nexus7. Last but not least, the synchronization arrow icon is upscaled while still being animated. Upscaling the animated PNG, in fact, took the most time of all this.
Here are some new screenshots. I purposely made one screenshot that shows the menu rendering issue; the menu is somewhat translucent and only the text is painted.
Overall, I am quite happy as it is right now. There are still issues and probably lots of things can be improved; having proper touch gestures and multi-touch support, e.g., would be awesome. But at least it turns out to be quite usable right now. I suggest that you install Okular along with Zotero. From my experience Okular works very well for viewing the stored *.pdf files.