I added OpenType features to both Talapanna, and a few more ligatures to complete the set. I remapped the Gothic capitals to a different position in the PUA for greater consistency.
The Gothic Drop Capitals can be accessed in programs that support OpenType features by using the "Initial Capitals" feature. The Bold typestyle uses a different set of Drop Capital designs.
The ligatures are now divided into two groups — ffi, ffl, fft, ffy, fty, ff, fi, fj, fl, fr, ft, fy, ky, tr, tt, ty, and longst are Standard Ligatures — cky, ck, ct, sp, st, tz, Qu, Th, AV, HE, LA, ME, NK, NT, OC, OG, OO, TL, TYcaps, TW, TTcaps, UB, and UD are discretionary ligatures.
The fonts include glyph substitions for superscripts and scientific inferiors (which bisect the baseline).
See this tutorial on Adding OpenType Features
to learn how to do this.