You do not need different program.
Do the following:
1. Unfold Undo WITHOUT checked "Apply open edges to 3D model"
2. Go to menu "3D ModelWindow" to item "Show Object List"
3. Select/unselect objects you want remove/remain in 3D window, for example in gravhammer you can select only object named "mesh 11 geometry" for remain only hammerhandle in 3D window.
4. NOTE! Before Unfold operation you can define any edges on 3D model view as Open/Closed edge. To enter "Pick open/closed edge" mode go to menu "3D ModelWindow" to item "Edit Mode" -> "Pick Open Edge." Now you can define any edge as you want open or closed. It gives you possibility to define every face in model as particular paper piece! There will be a LOT of small pieces, but at least you CAN PRINT them on standard paper.
5. UNFOLD! without "Auto" checked - it will unfolded by YOUR defined edges in previous step. Mostly.
6. SCALE!
7. Change all flaps width.
8. If you can - use BIG printer for big details. Eg A3 format. Or plotter with roll paper, on roll you can get A0 prints

If you can not - there is no other way than split parts and spread them on several pages. To put them together - use your creativity. If you can not - buy the assembled thing already!
Be happy