If you want to use your mouse wheel to zoom copy the following text into your actionmaps.xml in C:\Games\Piranha Games\MechWarrior Online\USER\Profiles\username\ (the file will open with notepad)
<action name="m_toggle_zoom_mode">
<rebind device="keyboard" input="mwheel_up" index="4" defaultInput=""/>
</action>
You want to put it after the following:
<ActionMaps Version="10">
<actionmap name="mech">
It is not overly elegant but it works, basically as you click your wheel forward it will scroll through the zoom levels.
<action name="m_toggle_zoom_mode">
<rebind device="keyboard" input="mwheel_up" index="4" defaultInput=""/>
</action>
You want to put it after the following:
<ActionMaps Version="10">
<actionmap name="mech">
It is not overly elegant but it works, basically as you click your wheel forward it will scroll through the zoom levels.