Save: Click the save icon or press Ctrl/Cmnd-S.
Load: drag and drop the .json file from your computer over the character sheet.
Print: Ctrl/Cmnd-P or right click. You can toggle printer-friendly mode from the menu bar.
The sheet is sized for A4, and the 5th page is just the background.
Edit: click on the various parts of the sheet to edit. Many entries are self-filling.
Class/Level: Drop-down menus divided by Class Group. The level reads the class group directly above for THAC0 and Saves.
Left Click on the level area to raise by one, and right click to reduce it.
House Rules, Dual/Multi: My house-rules engine is on by default. It mostly just interacts with the Dual/Multi Class button.
That button mostly tells the sheet how to calculate HP.
Auto/Manual HP: By default HP is auto-calculated using the average dice result, rounded up,
except for the first level which is max HP; all warrior classes get 6.
If you want to roll or do it differently, just type in your result and it will set HP to manual. You can always set it back to auto by choice.
Movement: Auto-calculates encumbrance from your Strength score. Number in Parentheses next to "Base Rate" is the total weight from Gear,
and the values below are your encumbrance levels.
Thief Skills: The bottom space is where you should put your base, racial, gear bonuses, and spent %. The top number is auto-calculated from your armor and Dex.
Turn Undead: If letters start showing up you should take a look at pgs.136-137 in the 2E PHB.
Spells: you can memorize and cast spells by toggling the button in the upper right. Click the spell name to cast.
Psionic Powers: you can edit and use psion powers after toggling the button.
Click the PSP Cost and Mntn'c (Maintainence) Cost to reduce that from your total.
Portrait: to add a portrait mouse over the top right side of 'Notes' and click the button.
Exit Help: Click anywhere outside of the "?" and this pop-up to close it.