The arrests were made on Monday.
Més and Podemos want Joan Gual de Torrella to be dismissed.
The head of Spain's Attorney-General's office in the Balearics is also under investigation.
Coinciding with Cursach's appearance was a demonstration outside the court involving some 300 people against "corruption in the court of instruction".
The National Police have presented the judge with an extraordinary analysis of systematic corruption at Palma town hall.
"I was finally able to testify before the judge about things which I deny. I responded to all questions with honesty and by telling the whole truth."