Stop build on first error

The vsCommandEvent also contains this feature and you should use this documentation, however with next notice:

Instead of "Errors-Build" event, you should configure the Output window tab:

variant	Guid	Item	Condition	Type
№ 1	`{1BD8A850-02D1-11d1-BEE7-00A0C913D1F8}`		`\s+error\s+([^:]+):`	Regexp
№ 2		`Build`	`\s+error\s+([^:]+):`	Regexp

if you need control of errors and warnings, use for example:

Condition	Type
`\s+(?:error\|warning)\s+([^:]+):`	Regexp

How to get this error/warning

If also need getting of this data, you should use SBE-Scripts engine, for example:

#[( #[OWP out.Warnings.Count] > 0 ){
    ... #[OWP out.Warnings.Codes]
}]

...
#[OWP out.Errors]

see OWPComponent for details.