For AllMovie_new script I found the way, defining custom field and the codes would be (for example):
Allmovie script:
//Get ~mfURL~ or ~URL~
endPos := Pos('"><span>overview</span></a>', HTML);
if endPos > 0 then begin
curPos := PrevPos('href="/movie', HTML, endPos);
AddFieldValue(mfURL, BASE_URL + Copy(HTML, curPos + 6, endPos - curPos - 6));
end else
AddFieldValue(mfURL, MovieURL);
AddCustomFieldValueByName('AllMovie.com', '<link url="' + MovieURL + '">AllMovie.com</link>');
Skin:
<row>
<column space="0" halign="left" autosize="true" valign="top">
<label>
<font>
<color>$000000</color>
<bold/>
</font>
<caption>Other URLs: </caption>
</label>
<custom field="AllMovie.com" linkcolor1="$338900"/>
</column>
</row>
Still, the OP question stands if it's possible to import urls in "url" field in such way.