How do unpack a custom format rpa

[pet345]

What did you try to open the archive with unrpa, and how did it fail?

Please copy and paste or screenshot the complete output from unrpa if it gave any.

Files needed to add support

Where it is legal and possible to do so, please:

• Provide the smallest possible archive that doesn't work.
• Provide renpy/loader.py.
  If you are unable to, please give us details on where we can find an example archive.

Additional context

Hello Lattyware
I have a game I want to unpack, but the format seems to be custom
This game Renpy's version should be 7.3.5.606
In loader.py I know what code it

As seen in the picture(I have to obliterate the code name,the full name has been sent to gmail),Although it is very similar to the encryption method of RPA-3.0, the red circle of OFFSET is different

This is the error result

[XELINQUENCY]

ahh, i've seen this type of enencryption before. i manually changed '000000000045a3ca' in the rpa package into '0000000000045a3c' ,and the code name back to 'RPA-3.0' in a hexadecimal text editor, and unrpa worked well.
i think "l[8:23]"(your first circle) read the 8th bit to the 22nd, so the last 'a' has no meaning. the offset should be move back one bit.
by the way, what we tried to unpack may be the same game :)