(1) The launch page will automatically capture all incoming query parameters, all query parameters will be preserved and automatically appended to any outgoing URL.
(2) The _script_ however can only make use of _at most_ *two* query parameters and record them in the data file(s):
- One to use as subject ID (that would be the one that stays the same for each subject), and
- One to use as group number.
The latter -- the group number -- must usually be numerical and is typically used to assign between-subjects conditions in the script (e.g. the order of compatible vs incompatible blocks in the IAT). The 2nd Respondi query parameter is probably unsuitable for that.