how to transform array to sequence - vector3d

dear group,
I stumble over two stupid problems.  [I use wxMaxima 5.12] 

(Despite of the very new function vector in package draw.lisp, version 1.9 from Mario, I
have the following question.)

1. If I define a simple user function vector3d as follows:

vector3d(a,b) :=  block( 
                  points_joined = true,
                  point_type = 6, point_size=1,
                  points([a,b]),
                  point_type = 9, point_size=2,
                  points([b]) )$

and call

vector3d([1,2,3],[2,4,1]);

.. so the function gives back the last entry 'points_joined = false' as return value
(which results in an error), but I need the *whole* sequence of commands inside block as
return value.

2. Similar, to define a line in 3D and to plot it I try:

Line : [2,3,0]+t*[1,-2,1];
draw3d( parametric(Line ,t,-2,2) )

.. but instead of   [2+t,3-2t,t] 
I need the sequence  2+t,3-2t,t  as return value resp. as input for parametric().

Which Maxima concept solves these similar problems?
Any hint would be very welcome. Sorry, if the question should be too simple.

HTH Wolfgang