Can't adjust the position of the inline equation inputed by TexMath plugin

Following is my libreoffice information:

Version: 5.1.4.2
Build ID: 1:5.1.4-0ubuntu1
CPU Threads: 8; OS Version: Linux 4.4; UI Render: default; 
Locale: en-US (en_US.UTF-8)

I use TexMath plugin to insert math equation in my Chinese document. But the inline equation, which is SVG image, can not keep in the center of the row. I adjust the inline equation position to the center of the row and check the position protect box in the Position and Size dialog. But after I save the document and then open it again, the position of the inline equation recover to the underline of the row. So how to fix this problem?

My document is a microsoft word document

When you use any foreign format, it is expected that some formatting (or even contents) may be distorted on round-trip. This may be due to either imperfection of import/export algorithms, or to the external format’s inability to store requested formatting/contents.

The latter seems to be the case here. When I insert an image to Writer document anchored as character, and set its vertical alignment centered to line, saving to native ODT gives expected good results. But saving to OOXML gives file that doesn’t have the desired alignment when open both in Writer and in Word. When I try to find any formatting option to make it properly aligned in Word, I cannot find one: looks like Word (and its native format) don’t have this ability. So, this isn’t a LO fault, but the format limitation, and wrong choice of saved format.

BTW: when Word imports ODT with properly aligned image, it drops the vertical alignment as well (although in this case, the formatting information is definitely saved in file).