I myself dont use c-script, but did do some c-script->lite-c conversions in the past.
So Im helping in lite-c in my head, then converting to c-script as I type my posts.
So there may be some conversion errors there.

For instance, the 'bad or missing parameter' error MAY be due to both versions of 'moveit'
MAY need parameter brackets after thier names. eg "moveit()" instead of just "moveit".
In lite-c you need to, but it seems optional in c-script.
Put em on and try and see if the error goes away.

Anyway, regardless of the brackets issue, if the second one didnt work, there are several possible reasons.
1> The "moveit" function is not being run.
2> The player pointer is not pointing to your player entity.
3> The player is a physics entity, and so cannot be moved with simple co-ordinate adjustments.
4> There is another action somewhere limiting the players movements in the x direction.

I think options #1 or #3 are the most likely causes...

So unless you can supply some of the code then I cant help out more...
Say, the opening part of the players action? (up to the start of its while loop).
Or are you using the templates? In that case try replacing "player" with "plBiped01_entity" in the "moveit" function.
Otherwise Im out of ideas of how to help.