First of all, many thanks to @fancy__04 for reporting this issue.

So basically in ‘Manual Mode’ there is a bug when attempting to redefine a custom payload in case the first attempt failed, for any reason that might be.
A simple example of when that can be caused, is by mistyping the filename of the custom payload.
The bug relies in the fact that the buffer holding the previous name is not re-initialized. This means that if the next filename is shorter than the previous one, then the extra characters of the previous name will remain ‘appended’ in the current one.
This basically would lead again to an invalid name until another valid filename longer or equal to the first one is set. This does not apply in ‘Auto Mode’ as there the buffer is correctly re-initialized when needed.
A fix for this issue will be applied in the upcoming Shellter v6.8.

Cheers,
kyREcon

Howdy, …long time no see!

Someone was kind enough to report a bug in the command line parser that is triggered when processing the ‘––reflective <FunctionName>’  switch/<parameter>.
It seems that this bug was introduced around version 5.x, while applying some updates in the command line parser.
What this means for you, is that if you want to use a reflective dll as a payload, then you need to do this from manual mode or auto mode without using the command line, until the fix is applied.
What this means for me, is that I have to release an update whenever possible…,most probably somewhere around mid-to-end of September. ;0)

Cheers,
kyREcon