[TheRaven81]

I was using this line, for my image:

<img alt="page005_image2" width="181px" height="136px" src="../Images/page005_image2.png" style="float: right; margin-left: 10px; margin-bottom: 10px;" />

Using this line in Sigil 0.7.4, I got these errors in validation:

value '136px' does not match regular expression facet '[-+]?(\d+|\d+(\.\d+)?%)'
value '181px' does not match regular expression facet '[-+]?(\d+|\d+(\.\d+)?%)'

This was fixed by moving those entries(width and height) into the style section of the line:

<img alt="page005_image2" src="../Images/page005_image2.png" style="float: right; margin-left: 10px; margin-bottom: 10px; width: 181px; height: 136px;" />

After doing this, the errors disappeared.

Hopefully this helps someone having the same issue.