Prescribed displacement for ASE moving springs

Hello again,

I would like to prescribe a displacement history in the z-direction for a node located on the top of a moving sprung-mass as seen in the figure below in order to simulate track irregularities, and I am not sure how to do this. The idea is the node with the mass will displace in the z-direction while it moves, relatively to the displacement induced by the moving spring and the beam interaction.

The displacement can be defined in sofiload, but when I run the loadcase defined in sofiload in conjuntion with the moving spring, it seems that only the moving sprung results alone are produced. Do anyone have any suggestions?

Edit: this is the teddy code:

+prog sofiload urs:11.13
head Loading
lc 3 type none
node no 101 type wzz 100[mm];func 1/20 1 0 0 0;
end

+prog ase urs:11.12
head Initate contact
syst prob nonl
movs grp 3 type 1 from 1 to 2 inc auto L0 1.5
grp 1 facd 0;
grp 2 facd 1;
lc 2 titl ‘Static’;
end

+prog ase urs:11.7
head Dynamic Analysis of moving spring
syst prob nonl plc 2
grp 1 facd 0;
grp 2 facd 1;
grp 3 facd 0;
step n 100 dt 8.99e-3 bet 0.25 del 0.5 the 1
lc 3 ;
v0 grp 2 vx 27.778 ;
end

Best regards,
Fredrik