Support
Email support@sheetvane.com and include your macOS version and, if possible, a description of what you were doing. Please do not send spreadsheets that contain private data.
Quick answers
What is Filter? It adds ▾ buttons to your header row so you can show only the rows you want. Other rows are hidden, never deleted. Press ⇧⌘L.
Where are all the commands? Press ⌘K and type. Press ⌘/ to see every keyboard shortcut.
I opened an .xlsx and some feature is missing. Sheetvane supports the common features (formulas, styles, filters, validation, conditional formatting, merged cells). Charts and comments are not saved inside .xlsx files yet.