If you take a look at the Settings file, you'll see that it explains how to achieve special results (such as a scattering of rapid-fire spurts, or a single sustained "firehose" spurt). It's expected that users won't actually use these extreme settings in-game (because they're goofy), but they help to illustrate the flexibility of the mod. You might try out the "firehose" mode, and then choose settings which are much closer to the default (but still delivering a few extra-long spurts during each orgasm).
The source code is included in the 7z archive.
The simplest solution is to move the morecumspurtV5settings.txt file into the main Settings subfolder of your SDT folder. It will then be available regardless of whether you load the file manually or via Character Folders (including $INIT$).