ISSUE RESOLVED Upon going to the Preview tab of the custom character sheet editor, nothing is displayed. About half of the time, the HTML and stylesheets will load into the document for the preview, but regardless, nothing will appear. I believe this error may be related to the ace.js library, as it is throwing warnings which I have never seen before. Log file and screenshots are in the Google Drive folder here. Also in that folder is a screenshot of what the character sheet looks like in-game at this time (expected behaviour). To replicate: Go to the Game Settings of a campaign (make sure you have a Pro subscription) Choose the Custom character sheet option Enter HTML and Stylesheet Go to the Preview tab System specs: Windows 7 64-bit Chrome 57.0.2987.133 Javascript and Cookies enabled Flash disabled I should mention that I have followed through with the Solving Technical Issues guide, and am posting this in compliance with Step 4.