在线求助max dwg格式转换为prt格式的方法 ？

在线求助max dwg格式转换为prt格式的方法 ？
QQ：4330058

直接转换时，很小的模型可以转换，模型一大就出错？怎么回事？

是这样的提示 图片：

While reading dxf file tmp_dwg.dxf
the following unsupported items were encountered:

line number 848:   Unknown group code: 370.
line number 860:   Unknown group code: 290.
line number 876:   Unknown group code: 290.
line number 880:   Unknown group code: 380.
line number 884:   Unknown group code: 290.
line number 896:   Unknown group code: 290.
line number 1474:   Unknown group code: 290.
line number 1476:   Unknown group code: 370.
line number 1478:   Unknown group code: 390.
line number 1496:   Unknown group code: 290.
line number 1498:   Unknown group code: 370.
line number 1500:   Unknown group code: 390.
line number 1792:   Unknown group code: 277.
line number 1794:   Unknown group code: 278.
line number 1796:   Unknown group code: 279.
line number 1826:   Unknown group code: 371.
line number 1828:   Unknown group code: 372.
line number 14606:   Unknown group code: 390.
line number 14632:   Unknown group code: 390.
line number 14646:   Unknown group code: 390.
line number 14674:   Unknown group code: 390.
line number 135600:   Entity thickness is not implemented.
line number 400436:   Entity thickness is not implemented.
line number 400470:   Entity thickness is not implemented.
line number 1181964:   Entity thickness is not implemented.
line number 1181998:   Entity thickness is not implemented.
line number 1317804:   Entity thickness is not implemented.
line number 2137432:   Entity thickness is not implemented.
line number 2137466:   Entity thickness is not implemented.
line number 2394418:   Entity thickness is not implemented.
line number 2394452:   Entity thickness is not implemented.
line number 3164802:   Entity thickness is not implemented.
line number 3164836:   Entity thickness is not implemented.
line number 3198840:   Entity thickness is not implemented.
line number 3198874:   Entity thickness is not implemented.
line number 3358604:   Entity thickness is not implemented.
line number 3358638:   Entity thickness is not implemented.

先在CAD中转换为dxf后再在PROE中转换LOG文件提示错误如下：
While reading dxf file D:\0116w.dxf
the following unsupported items were encountered:

line number 848:   Unknown group code: 370.
line number 860:   Unknown group code: 290.
line number 876:   Unknown group code: 290.
line number 880:   Unknown group code: 380.
line number 884:   Unknown group code: 290.
line number 896:   Unknown group code: 290.
line number 904:   Unknown group code: 290.
line number 1204:   Unknown group code: 370.
line number 1206:   Unknown group code: 390.
line number 1226:   Unknown group code: 370.
line number 1228:   Unknown group code: 390.

谁知道这些错误怎么解决？？？