您好,我没有安装您这个版本,我的电脑上安装的20.1版本,没有出现您说的这个问题,建议安装最新版本测试下,谢谢。
如果您之后有问题,可以联系FlexSim中国总代理商:技术支持邮箱support@csn-bj.com
If the problem still exists, after you have started the program FlexSim anew from your desktop or start menu, then I think it is graphic problem. There is an article here to cope with graphic problems.