I tested again with more than 50 reservation in my local. It works fine.

Following code mean use setting value "excel_max_rows=xxx" in preferences when assigned.
$max_rows=eguide_form_options('excel_max_rows', 40);

If not set use default value 40.
So, If you are already set value in preferences, default value change noting effect.
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安冨 伸浩 (マイサイト管理人)