Don't know exactly what went wrong for you. Here's a simple example:
<canvas>
<!-- http://openlaszlo.org/pipermail/laszlo-dev/attachments/20060202/b468da65/resizestateminmax.obj -->
<class name="resizestateminmax" extends="state">
<!--- @keywords private -->
<attribute name="xroffset"
value="$once{this.x - this.width + this.getMouse( 'x' )}" />
<!--- @keywords private -->
<attribute name="width"
value="${Math.min(
Math.max(Math.max((this.immediateparent.getMouse( 'x' )- xroffset),0), minwidth),
Math.min(Math.max((this.immediateparent.getMouse( 'x' )- xroffset),minwidth), maxwidth))}" />
<!--- @keywords private -->
<attribute name="yroffset"
value="$once{this.y - this.height + this.getMouse( 'y' ) }" />
<!--- @keywords private -->
<attribute name="height"
value="${Math.min(
Math.max(Math.max((this.immediateparent.getMouse( 'y' )- yroffset),0), minheight),
Math.min(Math.max((this.immediateparent.getMouse( 'y' )- yroffset),minheight), maxheight))}" />
</class>
<view x="50" y="50" width="500" height="500" bgcolor="blue" >
<view width="100" height="100" bgcolor="red" onmousedown="this.dragger.apply()" onmouseup="this.dragger.remove()">
<dragstate name="dragger"
drag_min_x="0"
drag_min_y="0"
drag_max_x="${this.parent.width - this.width}"
drag_max_y="${this.parent.height - this.height}" />
<resizestateminmax name="resizer" >
<attribute name="minwidth" value="50" />
<attribute name="minheight" value="50" />
<attribute name="maxwidth" value="${this.parent.width - this.x}" />
<attribute name="maxheight" value="${this.parent.height - this.y}" />
</resizestateminmax>
<view width="25" height="25" bgcolor="green" align="right" valign="bottom" onmousedown="this.parent.resizer.apply()" onmouseup="this.parent.resizer.remove()" />
</view>
</view>
</canvas>