No text layout. The package shapes runs of text; it does not split a text into runs, break lines, align paragraphs or order bidirectional text. Meziantou.Framework.Imaging does, and Meziantou.Framework.Unicode has the algorithms to write your own.
No rasterization. Outlines are given as lines and curves; filling them with pixels is up to the renderer.
No decoding of bitmap glyphs. The images of sbix and CBDT glyphs are given as encoded data.
Not supported: glyphs in SVG (SVG table), fonts without outlines (bitmap-only fonts), PostScript Type 1 fonts, the hints of CFF outlines, the variation of the TrueType hinting values (cvar), and the metadata and private blocks of WOFF and WOFF2 files.
AFM files: the multiple master (AMFM) and composite (ACFM) metrics files are not supported.
Low-level API. The public API is the one the Imaging, WebPlatform and Pdf libraries use; update the packages that use it together.
Meziantou.Framework