Die Stornierungsfrist gilt für die Veranstaltungstechnik.

Because the head noun is Frist, and Frist is feminine in German: die Frist.

Stornierungsfrist is a compound noun:

• Stornierung = cancellation
• Frist = deadline / time limit

In German, the last part of a compound decides the gender. Since Frist is feminine, the whole word is feminine too:

• die Frist
• die Stornierungsfrist

Here it is also the subject of the sentence, so die is the nominative feminine article.

Literally, it is something like cancellation deadline or cancellation period.

It is made up of:

• Stornierung = cancellation
• Frist = deadline, time limit, fixed period

So Stornierungsfrist refers to the period or deadline within which a cancellation is possible.

Gilt is the 3rd person singular present tense of gelten.

The verb gelten often means:

• to be valid
• to apply

In this sentence, gelten für means to apply to or to be valid for.

So:

• Die Stornierungsfrist gilt für ... = The cancellation deadline applies to ...

It is gilt because the subject is singular:

• die Stornierungsfrist = one deadline

Compare:

• Die Regel gilt. = The rule applies.
• Die Regeln gelten. = The rules apply.

Because für is a preposition that always takes the accusative case.

Veranstaltungstechnik is feminine:

• nominative: die Veranstaltungstechnik
• accusative: die Veranstaltungstechnik

For feminine nouns, the article die stays the same in nominative and accusative, so you see:

• für die Veranstaltungstechnik

A learner often expects a visible case change, but here the form happens to stay the same.

Veranstaltungstechnik is another compound noun:

• Veranstaltung = event
• Technik = technology / technical equipment / technical side

Depending on context, it can mean:

• event technology
• technical equipment for an event
• event production technology
• the technical side of an event, such as sound, lighting, staging, etc.

So it is broader than just one machine or device. It often refers to the whole technical area connected with an event.

In German, some nouns are used as collective or abstract singulars even when they refer to a whole area or set of equipment.

Veranstaltungstechnik works like that. It refers to the field or category as a whole, not necessarily to one single object.

English does something similar with words like:

• technology
• equipment

Those are often singular in form even though they cover many items.

German can say that, but gelten für is a very natural and common way to express the idea.

So these are both possible in many contexts:

• Die Stornierungsfrist gilt für die Veranstaltungstechnik.
• Die Stornierungsfrist ist für die Veranstaltungstechnik gültig.

The version with gilt für is usually more direct and idiomatic when talking about rules, deadlines, regulations, and conditions.

No, this is a very standard German main-clause word order:

• Die Stornierungsfrist = subject
• gilt = verb in second position
• für die Veranstaltungstechnik = prepositional phrase

German main clauses usually put the finite verb in position 2. Here the subject comes first, so the verb comes right after it.

Structure:

• [Subject] [Verb] [Rest]

Because in German, all nouns are capitalized.

In this sentence, the nouns are:

• Stornierungsfrist
• Veranstaltungstechnik

This is normal German spelling and one of the first things English speakers notice, since English only capitalizes nouns in special cases.

Not always. They are related, but they are not the same.

• Stornierung is usually a cancellation of a booking, reservation, order, or planned service.
• Kündigung is usually a termination or notice of termination, often for contracts, jobs, subscriptions, or rental agreements.

So Stornierungsfrist is appropriate for things like bookings or event-related services.
Kündigungsfrist would be used more for contracts and formal ongoing arrangements.

A few natural paraphrases are:

• Die Stornierungsfrist gilt auch für die Veranstaltungstechnik.
  if you mean it also applies to the event technology

• Für die Veranstaltungstechnik gilt die Stornierungsfrist.
  same meaning, but with emphasis on für die Veranstaltungstechnik

• Auch die Veranstaltungstechnik unterliegt der Stornierungsfrist.
  more formal: The event technology is also subject to the cancellation deadline

So the original sentence is already correct and natural, but German offers several ways to shift emphasis.