lb5 352 v32 win10 mainwin locate needs pre-printed field

[tsh73]

If you print a field into mainwin, locate seems to work as expected
getting this
0 1 2 % 4 5 6 7 8 9
0 1 2 % 4 5 6 7 8 9
0 1 2 % 4 5 6 7 8 9
0 1 2 % 4 5 6 7 8 9
******%** 5 6 7 8 9
0 1 2 % 4 5 6 7 8 9
0 1 2 % 4 5 6 7 8 9
0 1 2 % 4 5 6 7 8 9
0 1 2 % 4 5 6 7 8 9
0 1 2 3 4 5 6 7 8 9

But if you uncomment first line, skipping previous printing, locate does not work as expected

       %%


    %

    %

    %
(actually weird thing stars if you have pre-printed field 20x10 as here and try to locate horisontally at 30)

'goto [1]
for i =1 to 10
   for j = 0 to 9
       print j;" ";
   next
   print
next
'input a$
[1]
'print "#"
'input a$
for i = 1 to 9
locate i,5  'horizontal
print "*";
next
'input a$
for i = 1 to 9
locate 7,i  'vertical
print "%";
next