PDF file documentation, examples and video tutorials are available.

Get to official X-Muscle System support video channel

Watch the demo

https://www.youtube.com/watch?v=ee7kcqsx_Ek 

Changelog: 

Software and Documentation Updates 

versions 2.4.7

• fix muscle pinning not listed
• fix muscles not xmirrored correctly

versions 2.4.0

• updated for Blender 3.0
  
  

versions 2.3.9

• fixed localization bugs
• added undo support (will not randomly crash on CTRL+Z, supports undo correctly)
• Improved compatibility with Blender 2.9. Fixed random installation issue,
• bugfixes
  

versions 2.3.7

• added Muscle Offset feature

versions 2.3.4

• fixed API changed in Blender 2.9x

versions 2.3.3

• fixed compatibility conflict with BlenderKit add-on,
• fixed compatibility conflict with Avastar2 add-on

versions 2.2.9

• fix microControllers not working
  
  

versions 2.2.7

• added localization compatibility
  
  

versions 2.1.9

• internal engine improvement muscle bulge stability (affects only new entities)

versions 2.0.2

• fix non responsive properties

version 2.0.1

• fix add microController to skin error

versions 2.0.0

• Blender 2.8 port

versions 1.9.7

• new muscle strip type added
• documentation Update

versions 1.9.3

• microControllers now x-mirrors correctly when muscles are using pinning, bugfix

versions 1.9.0

• new Isolate Selected Muscles feature,
• documentation Update

versions 1.8.9 and 1.8.9a-e:

• fix exception access violation when Multires was used without shapekeys, a
• full support for advanced features: bendy muscles and muscle pinning including X-Mirror support, c
• better mirroring accuracy when scaling is used, c
• important bugfixes, c
• X-Mirror support for Bendy Muscles
• Anatomy Bundle added, c
• allows to manually reattach muscles attached with auto-aim to other bones and still successfully bind them with the skin. (more flexible workflow in sacrifice of auto-weight painting), d
• allows to successfully finish binding all the muscles to the skin even when corrupted microController mechanism is detected (accidentally deleted or omitted on muscle duplication), d
• new Muscle Pinning Panel powerful Manager, e
• enable and disable viewport/render muscle pinning, e
• add/remove muscle pins feature, e
• select pins toggle feature, e
• reset selected pins feature, e
• minor bugfixes, e
• documentation update, e

version 1.8.7 and 1.8.7a:

• improved Vertex Group management
• added full support for rename feature after skinning for Vertex Groups and drivers
• fixed multi-rename failed to work in some cases
• fixed new muscle Shape is now added to active scene layer only instead to all selected layers
• change skin model to Object Mode on Micro_Controller toggle
• fix muscle remains selected after Auto-Aim create
• fix remove drivers from skin after Micro_Controller disabling
• muscles will now remain selected after Micro_Controller enable/disable toggle
• Micro_Controllers will now work even if character object is hidden
• Documentation Update

version  1.8.3:

• significantly improved freestyle weightpainting x-mirror
• fix tension value for Micro_Controller on  x-mirror
• fix Micro_Controller Set option works now for any Mode 
• fixed x-mirror muscles if some its parts are hidden
• minor bugfixes

versions  1.7.9 a-e:

• fixed critical exception on Micro_Controller deletion, final fix, e
• muscle size to scale along its local YZ fix, d
• some default values for muscle properties fix, d
• perfect symmetry final fix, c
• perfect symmetry fix (muscle "System" part orientation now mirrored correctly), b
• fixed property viewport refresh for selected muscle when all parts are selected, a

version  1.7.9:

• Quick Start - Video Tutorial
• added full Micro_Controller X-Mirror support feature with X-Mirroring Vertex Groups
• Documentation Update
• default muscle create type set to Manual at file startup
• solved invalid orientation for Micro_Controller in particular scenarios
• now X-Muscle System works correctly with scaled rig
• improved pretty Vertex Group naming (dedicated unique naming)
• fixed unintended settings deletion for all muscles in exceptional scenarios
• resolved x-mirror with applying body to mesh inverted order
• Multi-Set support for microControllers feature

Besides new features, this Update contains many bug fixes.

version  1.7.3:

• added Select Single Muscle function and UI button
• fixed cleanup orphaned microController
• added Allow_Duplication and Keep_over_Subdiv setting to the UI
• Multi-Rename feature added
• Allow Duplications  feature added with support for X-Mirror and skinning
• fixed critical exception on microController deletion
• Documentation Update
• optimized operation with subsurf in stack
• Keep over Subdiv feature added
• autobind microController to the skin feature

Besides new features, this Update contains stability, performance improvements and better scene management.