When I open the attached document test.odt (with one frame anchor type "page"
width: 100%, height: 100%; and another frame anchor type "frame" width: 50%,
height: 50%), it is displayed correctly. When I open the dialog Format->Frame,
he shows me width:50% and height:25%. When I click OK without making any
changes, the height is halved to 25%. I can repeat this (opening the dialog and
click OK) and each time the hight is halved: 12%, then 6%, then 3%, then 1%.

I don't know much about the file format, but values for svg:height in the file
test.odt are also a litte bit strange:

 <office:body>
  <office:text>
   <office:forms form:automatic-focus="false" form:apply-design-mode="false"/>
   <text:sequence-decls>
    <text:sequence-decl text:display-outline-level="0" text:name="Illustration"/>
    <text:sequence-decl text:display-outline-level="0" text:name="Table"/>
    <text:sequence-decl text:display-outline-level="0" text:name="Text"/>
    <text:sequence-decl text:display-outline-level="0" text:name="Drawing"/>
   </text:sequence-decls><draw:frame draw:style-name="fr1" draw:name="Frame1"
text:anchor-type="page" text:anchor-page-number="1" svg:width="169.99mm"
style:rel-width="100%" svg:height="64.24mm" style:rel-height="50%" draw:z-index="0">
    <draw:text-box><draw:frame draw:style-name="fr2" draw:name="Frame2"
text:anchor-type="frame" svg:width="84.98mm" style:rel-width="50%"
svg:height="64.24mm" style:rel-height="50%" draw:z-index="1">
      <draw:text-box>
       <text:p text:style-name="Frame_20_contents"/>
      </draw:text-box>
     </draw:frame>
     <text:p text:style-name="Frame_20_contents"/>
    </draw:text-box>
   </draw:frame>
   <text:p text:style-name="Standard"/>
  </office:text>
 </office:body>
 
PS: When I construct the same document with 1.1 (attached as test1.1.sxw) and
then open it in 1.9.104, save it as odt (attached as test1.1.odt) and reopen it
with 1.9.104, there are no problems.

I'm working under linux - but under windows, there seem also to be problems...