There have recently been several postings in the Lounge with reference to the merits of Mozilla and, in separate postings, the benefits of a download accelerator such as DAP (Download Accelerator Plus).
DAP does not have a built in option to readily associate it with Mozilla (only IE, Netscape and Opera). However, the solution is not painful. The following instructions are from the DAP FAQ page:

How to integrate DAP into the Mozilla browser ?

1. Copy the file 'dapop.dll' from 'DAP' folder (C:Program FilesDAP) into the 'Plug-Ins' folder (C:Program FilesMozillaPlug-Ins)
2. Rename the copied file from 'dapop.dll' to 'npdap.dll'

Your DAP is now integrated into the Mozilla browser.

Have a Great day!!!