Thank you for confirming that updating to the current version helped with CSV export.
The CSV export functionality evaluates and exports selected data in grid point by default, the field [fea.grid.p] so the CSV data should have the column length "size(fea.grid.p,2)" if you did not change the export coordinates. The data evaluation itself is just the code
n_p = size(xp,2);
n_sdim = size(xp,1);
n_expr = length(expr);
data = [xp.', zeros(n_p, n_expr)];
for i=1:n_expr
data(:,n_sdim + i) = evalexpr( expr{i}, xp, fea, solnum );
end
where "expr" is a cell array of the expressions to evaluate, for example "{'u', 'v', 'w', 'p'}".