Preview of models that contain text fields (or at least parsed text fields) seems to be broken. Using the sample ejss files for the harmonic oscillator show the problem. Deleting the text fields results in other elements showing up. Nothing untoward seems to appear in the console output area.
I've attached another example where deleting allows proper display of the other element in that panel.
This doesn't seem to be a problem in EJS_5.01beta_141014, so it does seem to be a new bug.
