[Therion] Scaling of maps

Hi, I'm just redrawing a not too small cave in therion. The x- and y- extent is quite big, while having lots of small passages. In these passages a scale of 1:250 is still nice, however exporting in that scale exporting does not work due to the error: "error -- Map is too large for PDF format. Try smaller scale!" Is there a way to "scale down" export while keeping details? Especially gradient arrows and other symbols not looking good at 1:1000. I know that some details getting too small for printing, but it would love to have it on screen as one map... Best regards Wolfgang