How to desable automatic spaces before round barckets () ?

Depending on whether you want to change the default behavior, or if you want to change your current project formatting, in MonoDevelop (Changing default behavior won't affect current project!):

Default : Tools -> Options...

Current Project : Project -> Solution Options

then

Source code -> Code Formatting -> C# source code

open C# Format -tab on the right click "Edit" button

Select "White space" from in drop down list and uncheck:

Expressions -> Method invocations -> before opening parenthesis

Adter setting the preferences you want, go to Edit -> Format -> Format Document/Format Selection to apply the new rules to your files