It would be nice to have a complete list of all e-sword standard files/ file types available, their specific purpose and association, pinned somewhere in the forum.
The ones I question are the 8 below:
ComboList.ocx
custom.dic
headings.en
headings.es
headings.pt
localize.lanx
RichEdit.ocx
vsth_ae.the
Any informational post should also add the standard:
Bookmarks.lstx
journal.jnlx
markup.ovlx
study.notx
topic.topx
File types: .bblx .cmtx .dctx .devx .harx .lexi .lexx .mapx . refi .refx .topx .ttf
Thanks for any help. 
As there are versions of e-Sword for both Windows users and Apple/Mac users there are different file formats for each specific installation e-Sword.
For E-Sword versions 9 & 10 for Windows here are the module file types:
Bible (bblx)
Commentary (cmtx)
Dictionary (dctx)
Bible Reading Plan (brpx)
Devotional (devx)
Topic (topx)
Harmony File (harx)
Maps/Graphics (mapx)
Reference Libraty (refx)
Note (notx)
Journal (jnlx)
Memory (memx)
Markup (ovlx)
For Apple/Mac installations of e-Sword version 9,10 &11 here are the module file types:
Bible (bbli)
Commentary (cmti)
Dictionary (dcti)
Bible Reading Plan (brpi).
Devotional (devi)
Reference Library (refi)
Note Files (noti)
Topic Files (topi)
Lexicon (lexi)
e-Sword 11 for Windows reads all of the module formats for versions 9 & 10 for Windows as well as all of the Apple/Mac module formats
The 8 files in your list are files need for e-Sword to work properly:
headings.en
headings.es
headings.pt
The headings files allow e-Sword to properly display section headings in bible modules the .en extension is for English, .es extension is for Spanish, and the .pt extension is for Portuguese .
combolist.ocx is one of two active x controls that are installed with e-Sword the other is called richedit.ocx. Neither file is dangerous they are both part of what makes e-Sword run
The other 3 files custom.dic, localize.lanx and vsth_ae.the are also files needed in order for E-Sword to run properly
