Hi there, I'm using gretl to construct panels and load data in via the great join command - thanks for developing this feature! When I tried to save the final data file in the new gdtb format something went wrong. gretl saves a file but crashes when opening it. Below is the the hansl script to produce the error. In terms of the join command: a compound condition of four and more elements is not supported, or? Have a nice St. Nicholas' Day Leon #**************** set echo off set messages off nulldata 10 --preserve scalar Y1 = 2001 scalar Y2=Y1 + 25 #Level 1 matrix M1 = \ {510\ ;520} string file = "markers_Panel_" sprintf stamp "%d", abs(round(randgen1(z, 0, 1)*randgen1(z, 0, 1)*randgen1(i, 50, 200))) file += stamp file += ".txt" print file outfile "@file" --write loop i=1..rows(M1) --quiet loop j = Y1..Y2 --quiet printf "%g/%g\n", M1[i], j endloop endloop outfile --close scalar N = rows(M1) scalar T = (Y2-Y1+1) scalar counts = N*T nulldata counts --preserve setobs T 1:01 --stacked-time-series series BVNR = M1**ones(T,1) setinfo BVNR --description="Unit ID" series time = ones(N,1)**seq(Y1,Y2)' setinfo time --description="Years" delete index list lGroups = BVNR time discrete lGroups setobs BVNR time --panel-vars sprintf strY1 "%g", Y1 setobs 1 @strY1 --panel-time series time_gretl = $obsdate markers --from-file="@file" store "testPanel.gdt" open "testPanel.gdt" #store "testPanel.gdtb" #open "testPanel.gdtb" #************************