params can be None so for simplicity set it to {}

bt5/erp5_open_trade/SkinTemplateItem/portal_skins/erp5_open_trade/Alarm_updateOpenOrderSimulation.xml

@@ -53,6 +53,8 @@
             <value> <string encoding="cdata"><![CDATA[
 
 kw = {}\n
+if params is None:\n
+  params = {}\n
 \n
 last_active_process = context.getLastActiveProcess()\n
 \n

bt5/erp5_open_trade/bt/revision

-106
+107
\ No newline at end of file