Go to the Scripts List page (if you’re already in a script, touch the left-pointing Back arrow at the upper left):
Touch the App Settings icon at the upper left and toggle the spellcheck on:
Touch the screen to exit this window and touch a script to open it.
If a word is misspelled, it will have a dotted red line under it ("someome").
Touch the word and spelling choices will appear:
Touch the correctly-spelled word or choose to Ignore, Ignore All or Learn and the spellcheck bar will disappear.