I would have a few comments, but first I would like to understand your case a little better.
Are you sure you need a remote displacement? Wouldn’t be a simple “fixed value” constraint be sufficient?
Regarding the message, it is not an error message, just a warning:
The constraint can still be saved and you may run the analysis without any issues, but generally
in a nonlinear static analysis your load should usually be ramped in order for the nonlinear solver to be able to efficiently solve your problem by splitting it into multiple “less nonlinear” sub-steps. If you only have a scalar load value, at each time step the same equation is solved, so there is no point in running multiple time steps (which is usually done to gradually solve the nonlinearity as it otherwise would not be possible to be solved “in one step”).
You are right that the warning message content could be improved - I’ll take care of this one.