Help me to understand some lyrics (Shinedown - Her name is Alice)
1) What means "every creature lends themself"?
The verb "lend" is confusing me. What does it mean in that context?

2) "but now off with her head I fear is everyone's concern"
Does it mean "I fear that everyone want to cut her head off now"?

3) What does "unlocking the meaning" mean?

Shinedown - Her name is Alice

I invite you to a world where there is no such thing as time
And every creature lends themself to change your state of mind

Question

Help me to understand some lyrics (Shinedown - Her name is Alice)
1) What means "every creature lends themself"?
The verb "lend" is confusing me. What does it mean in that context?

2) "but now off with her head I fear is everyone's concern"
Does it mean "I fear that everyone want to cut her head off now"?

3) What does "unlocking the meaning" mean?

Shinedown - Her name is Alice

I invite you to a world where there is no such thing as time 
And every creature lends themself to change your state of mind <----- 1
And the girl that chase the rabbit drank the wine and took the pill 
Has locked herself in limbo to see how it truly feels 
To stand outside your virtue 
No one can ever hurt you 
Or so they say 

Her name is Alice (Alice) 
She crawls into the window 
Through shapes and shadows 
Alice (Alice) 
And even though she is dreaming, she knows 

Sometimes the curiosity can kill the soul but leave the pain 
And every ounce of innocence is left inside her brain 
And through the looking glass we see shes painfully returned 
But now off with her head I fear is everyone's concern <------------- 2
You see there's no real ending 
It's only the beginning 
Come out and play 

Her name is Alice (Alice) 
She crawls into to the window 
Through shapes and shadows 
Alice (Alice) 
And even though she is dreaming 
She's unlocked the meaning for you

Answer

this song is much to do with the book Alice in wonderland and it's sequel Through the looking glass, the latter I have yet to read, besides in here google is again out of order, so here please have my stingy contribution, a few guesses not worthing even one penny:

And every creature lends themself to change your state of mind <----- 1 
*lends themselves to: make themselves useful to.

But now off with her head I fear is everyone's concern <------------- 2 
*in Alice in wonderland there's a queen who always shouts 'off with his head' or 'off with her head' whenever and to whomever she feels like to punish, so this might be read as: I fear it's everyone's concern that the queen would want Alice's head still.

She's unlocked the meaning for you

Answer

1) lend itself to .... is good, suitable, or appropriate for that purpose. 

- Her voice lends itself well to (singing) opera. 
-The topics lend themselves to classroom discussion. 
-And every creature lends themself to change your state of mind. 
Every creature is suitable for changing your state of mind. 

2) "but now off with her head I fear is everyone's concern" 

The Queen of Hearts is a character from the book "Alice's Adventures in Wonderland" by Lewis Carroll. She is an angry monarch who sentences people to death for even the smallest offense. Her famous line which she repeats often is " Off with their heads!" When Alice is trying to escape she cries, "Don't let her get away! Off with her head!" 

The next line states: You see there's no real ending. Although the dream is over there is no ending to the story and Alice is still escaping from the Queen's order "Off with her head!", so her problem has now become everyone's concern. 

3) She's unlocked the meaning for you 

She has furnished a key for the meaning. If you unlock the meaning of a secret or mystery you find the explanation.