How it works. A sheet auto-saves in this browser once it has a name. Renaming a sheet renames its save. Use the tabs to move between the two pages. Print prints both pages of the current character, one per US Letter sheet, and Print Blank prints an empty pair. Export downloads every sheet as a JSON file and Import merges a file like that back in (a sheet with the same name is replaced). Nothing leaves your browser.
Worked out for you. Each characteristic's Current value is Initial + Advances, and its Bonus is the tens digit (S 34 gives SB 3). A skill is its characteristic's Current value + the skill's advances: your target number for a test. Wounds are SB + (2 × TB) + WPB, or (2 × TB) + WPB for Small characters such as Halflings, plus anything you enter (for example from Hardy). Walk is Movement × 2 yards and Run is Movement × 4; choosing a species fills in its Movement (Human 4, Dwarf 3, Halfling 3, Elves 5). Your encumbrance limit is SB + TB, your Corruption limit is TB + WPB, and total XP is current + spent. The Sturdy / other box adds to the encumbrance limit (2 per level of Sturdy) and Pure Soul / other adds to the Corruption limit (1 per level of Pure Soul). See Character Creation for building a character and the Dice Roller for your tests.
Sample sheets. Load sample characters adds all 64 characters from Sample Characters (one for every core career: fresh starters and veterans of all five species), replacing any saved sheet with the same name just as Import does and leaving your other sheets alone; you can also download the sample sheet file and import it yourself.