Alright. I'm not going to code it all up for you, but here's how I would go about doing it :
First of all, open up your script editor, and select the following script : Window_Skill
On line 75, you will see the following line of code :
self.contents.draw_text(x + 232, y, 48, 32, skill.sp_cost.to_s, 2)
Simply comment it (add a "#" in front of it), or remove it altogether and it will not write the skill SP cost anymore. That should take care of your first problem.
Moving on to the next one: showing (and updating) the SP cost at the bottom right corner in a window by itself. Note: my goal here is to help you, but also make sure you learn something. This isn't the script requests section.
If you follow these steps, you should be able to create a window that will be displayed at the bottom right corner.
Step 1) Create a new script named "Window_SkillCost". Inside, create a new class named "Window_SkillCost" which extends the class "Window_Help". ( class Window_SkillCost < Window_Help )
Step 2) In your Window_SkillCost class, create a "initialize" method. If you need help, try to look at Window_Help and see how its initialize method is done. Yours should be very similar. You should only have to modify the coordinates (x and y) and the size of the window.
Step 3) In your Window_SkillCost class, create a set_text method as follows :
def set_text(text, align = 1)
# Code here
end
This method will hold the code that will be used to draw the SP cost. For example you might call it like this : skill_cost_window.set_text(skill.sp_cost.to_s)
Step 4) Once your set_text method is done, go back into the Window_Skill class. Here, you have to add a new class variable which will hold a reference to a Window_SkillCost object. Then, in the draw_item method, you will call that class variable's set_text method with the current selected skill's sp cost. To obtain the current selected skill from the Window_Skill class, use the following line :
current_skill = self.skill
-----------------------
So, basically, what'd you have would be :
class Window_SkillCost < Window_Help
def initialize
super
# Set your coordinates and width/height
# e.g. : self.x = 32
# self.y = 32
# Delete your current contents object and create a new one
self.contents.dispose
self.contents = Bitmap.new( self.width - 32, self.height - 32 )
end
def set_text(text, align = 1)
# Code to display text goes here
end
end
That's the bare bones of your Window_SkillCost class.
In the Window_Skill class, remember, you need to edit the following methods : initialize and refresh.
In initialize, you'd add :
@window_sc = Window_SkillCost.new
And in the refresh method, before the end, you'd add :
@window_sc.set_text(self.skill.sp_cost.to_s)
Hopefully you can work the kinks out yourself. If you can't find the solution by yourself, than feel free to ask more questions.